Add integration to all targets (#29020)

dev/devicelab/bin/tasks/codegen_integration_mac.dart

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+import 'dart:io';
+
+import 'package:path/path.dart' as path;
+
+import 'package:flutter_devicelab/framework/adb.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+import 'package:flutter_devicelab/framework/utils.dart';
+import 'package:flutter_devicelab/tasks/integration_tests.dart';
+
+final Directory codegenAppPath = dir(path.join(flutterDirectory.path, 'dev/integration_tests/codegen'));
+
+Future<void> main() async {
+  deviceOperatingSystem = DeviceOperatingSystem.ios;
+  await task(createCodegenerationIntegrationTest());
+}

dev/devicelab/bin/tasks/codegen_integration_win.dart

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+import 'dart:io';
+
+import 'package:path/path.dart' as path;
+
+import 'package:flutter_devicelab/framework/adb.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+import 'package:flutter_devicelab/framework/utils.dart';
+import 'package:flutter_devicelab/tasks/integration_tests.dart';
+
+final Directory codegenAppPath = dir(path.join(flutterDirectory.path, 'dev/integration_tests/codegen'));
+
+Future<void> main() async {
+  deviceOperatingSystem = DeviceOperatingSystem.android;
+  await task(createCodegenerationIntegrationTest());
+}

dev/devicelab/manifest.yaml

@@ -76,7 +76,7 @@ tasks:
     stage: devicelab_win
     required_agent_capabilities: ["windows/android"]
 
-  codegen_integration_test:
+  codegen_integration_win:
     description: >
       Runs codegeneration and verifies that it can execute
       correctly.
@@ -84,6 +84,22 @@ tasks:
     required_agent_capabilities: ["windows/android"]
     flaky: true
 
+  codegen_integration_mac:
+    description: >
+      Runs codegeneration and verifies that it can execute
+      correctly.
+    stage: devicelab_ios
+    required_agent_capabilities: ["mac/ios"]
+    flaky: true
+
+  codegen_integration_linux:
+    description: >
+      Runs codegeneration and verifies that it can execute
+      correctly.
+    stage: devicelab
+    required_agent_capabilities: ["linux/android"]
+    flaky: true
+
   flutter_gallery_android__compile:
     description: >
       Collects various performance metrics of compiling the Flutter

dev/integration_tests/codegen/ios/Flutter/AppFrameworkInfo.plist

+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+  <key>CFBundleDevelopmentRegion</key>
+  <string>en</string>
+  <key>CFBundleExecutable</key>
+  <string>App</string>
+  <key>CFBundleIdentifier</key>
+  <string>io.flutter.flutter.app</string>
+  <key>CFBundleInfoDictionaryVersion</key>
+  <string>6.0</string>
+  <key>CFBundleName</key>
+  <string>App</string>
+  <key>CFBundlePackageType</key>
+  <string>FMWK</string>
+  <key>CFBundleShortVersionString</key>
+  <string>1.0</string>
+  <key>CFBundleSignature</key>
+  <string>????</string>
+  <key>CFBundleVersion</key>
+  <string>1.0</string>
+  <key>MinimumOSVersion</key>
+  <string>8.0</string>
+</dict>
+</plist>

dev/integration_tests/codegen/ios/Flutter/Debug.xcconfig

+#include "Generated.xcconfig"

dev/integration_tests/codegen/ios/Flutter/Release.xcconfig

+#include "Generated.xcconfig"

dev/integration_tests/codegen/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata

+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "group:Runner.xcodeproj">
+   </FileRef>
+</Workspace>

dev/integration_tests/codegen/ios/Runner.xcodeproj/xcshareddata/xcschemes/Runner.xcscheme

+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "0910"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+               BuildableName = "Runner.app"
+               BlueprintName = "Runner"
+               ReferencedContainer = "container:Runner.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <Testables>
+      </Testables>
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+            BuildableName = "Runner.app"
+            BlueprintName = "Runner"
+            ReferencedContainer = "container:Runner.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+      <AdditionalOptions>
+      </AdditionalOptions>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      language = ""
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+            BuildableName = "Runner.app"
+            BlueprintName = "Runner"
+            ReferencedContainer = "container:Runner.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+      <AdditionalOptions>
+      </AdditionalOptions>
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Profile"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <BuildableProductRunnable
+         runnableDebuggingMode = "0">
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "97C146ED1CF9000F007C117D"
+            BuildableName = "Runner.app"
+            BlueprintName = "Runner"
+            ReferencedContainer = "container:Runner.xcodeproj">
+         </BuildableReference>
+      </BuildableProductRunnable>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>

dev/integration_tests/codegen/ios/Runner.xcworkspace/contents.xcworkspacedata

+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "group:Runner.xcodeproj">
+   </FileRef>
+</Workspace>

dev/integration_tests/codegen/ios/Runner.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings

+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>BuildSystemType</key>
+	<string>Original</string>
+</dict>
+</plist>

dev/integration_tests/codegen/ios/Runner/AppDelegate.h

+#import <Flutter/Flutter.h>
+#import <UIKit/UIKit.h>
+
+@interface AppDelegate : FlutterAppDelegate
+
+@end

dev/integration_tests/codegen/ios/Runner/AppDelegate.m

+#include "AppDelegate.h"
+#include "GeneratedPluginRegistrant.h"
+
+@implementation AppDelegate
+
+- (BOOL)application:(UIApplication *)application
+    didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
+  [GeneratedPluginRegistrant registerWithRegistry:self];
+  // Override point for customization after application launch.
+  return [super application:application didFinishLaunchingWithOptions:launchOptions];
+}
+
+@end

dev/integration_tests/codegen/ios/Runner/Assets.xcassets/AppIcon.appiconset/Contents.json

+{
+  "images" : [
+    {
+      "size" : "20x20",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-20x20@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "20x20",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-20x20@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-29x29@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-29x29@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-29x29@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-40x40@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-40x40@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "60x60",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-60x60@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "60x60",
+      "idiom" : "iphone",
+      "filename" : "Icon-App-60x60@3x.png",
+      "scale" : "3x"
+    },
+    {
+      "size" : "20x20",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-20x20@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "20x20",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-20x20@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-29x29@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "29x29",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-29x29@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-40x40@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "40x40",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-40x40@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "76x76",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-76x76@1x.png",
+      "scale" : "1x"
+    },
+    {
+      "size" : "76x76",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-76x76@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "83.5x83.5",
+      "idiom" : "ipad",
+      "filename" : "Icon-App-83.5x83.5@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "size" : "1024x1024",
+      "idiom" : "ios-marketing",
+      "filename" : "Icon-App-1024x1024@1x.png",
+      "scale" : "1x"
+    }
+  ],
+  "info" : {
+    "version" : 1,
+    "author" : "xcode"
+  }
+}

dev/integration_tests/codegen/ios/Runner/Assets.xcassets/LaunchImage.imageset/Contents.json

+{
+  "images" : [
+    {
+      "idiom" : "universal",
+      "filename" : "LaunchImage.png",
+      "scale" : "1x"
+    },
+    {
+      "idiom" : "universal",
+      "filename" : "LaunchImage@2x.png",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "universal",
+      "filename" : "LaunchImage@3x.png",
+      "scale" : "3x"
+    }
+  ],
+  "info" : {
+    "version" : 1,
+    "author" : "xcode"
+  }
+}

dev/integration_tests/codegen/ios/Runner/Assets.xcassets/LaunchImage.imageset/README.md

+# Launch Screen Assets
+
+You can customize the launch screen with your own desired assets by replacing the image files in this directory.
+
+You can also do it by opening your Flutter project's Xcode project with `open ios/Runner.xcworkspace`, selecting `Runner/Assets.xcassets` in the Project Navigator and dropping in the desired images.
\ No newline at end of file

dev/integration_tests/codegen/ios/Runner/Base.lproj/LaunchScreen.storyboard

+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="12121" systemVersion="16G29" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" colorMatched="YES" initialViewController="01J-lp-oVM">
+    <dependencies>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="12089"/>
+    </dependencies>
+    <scenes>
+        <!--View Controller-->
+        <scene sceneID="EHf-IW-A2E">
+            <objects>
+                <viewController id="01J-lp-oVM" sceneMemberID="viewController">
+                    <layoutGuides>
+                        <viewControllerLayoutGuide type="top" id="Ydg-fD-yQy"/>
+                        <viewControllerLayoutGuide type="bottom" id="xbc-2k-c8Z"/>
+                    </layoutGuides>
+                    <view key="view" contentMode="scaleToFill" id="Ze5-6b-2t3">
+                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                        <subviews>
+                            <imageView opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" image="LaunchImage" translatesAutoresizingMaskIntoConstraints="NO" id="YRO-k0-Ey4">
+                            </imageView>
+                        </subviews>
+                        <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
+                        <constraints>
+                            <constraint firstItem="YRO-k0-Ey4" firstAttribute="centerX" secondItem="Ze5-6b-2t3" secondAttribute="centerX" id="1a2-6s-vTC"/>
+                            <constraint firstItem="YRO-k0-Ey4" firstAttribute="centerY" secondItem="Ze5-6b-2t3" secondAttribute="centerY" id="4X2-HB-R7a"/>
+                        </constraints>
+                    </view>
+                </viewController>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="iYj-Kq-Ea1" userLabel="First Responder" sceneMemberID="firstResponder"/>
+            </objects>
+            <point key="canvasLocation" x="53" y="375"/>
+        </scene>
+    </scenes>
+    <resources>
+        <image name="LaunchImage" width="168" height="185"/>
+    </resources>
+</document>

dev/integration_tests/codegen/ios/Runner/Base.lproj/Main.storyboard

+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="10117" systemVersion="15F34" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" initialViewController="BYZ-38-t0r">
+    <dependencies>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="10085"/>
+    </dependencies>
+    <scenes>
+        <!--Flutter View Controller-->
+        <scene sceneID="tne-QT-ifu">
+            <objects>
+                <viewController id="BYZ-38-t0r" customClass="FlutterViewController" sceneMemberID="viewController">
+                    <layoutGuides>
+                        <viewControllerLayoutGuide type="top" id="y3c-jy-aDJ"/>
+                        <viewControllerLayoutGuide type="bottom" id="wfy-db-euE"/>
+                    </layoutGuides>
+                    <view key="view" contentMode="scaleToFill" id="8bC-Xf-vdC">
+                        <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
+                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                        <color key="backgroundColor" white="1" alpha="1" colorSpace="custom" customColorSpace="calibratedWhite"/>
+                    </view>
+                </viewController>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="dkx-z0-nzr" sceneMemberID="firstResponder"/>
+            </objects>
+        </scene>
+    </scenes>
+</document>

dev/integration_tests/codegen/ios/Runner/Info.plist

+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>CFBundleDevelopmentRegion</key>
+	<string>en</string>
+	<key>CFBundleExecutable</key>
+	<string>$(EXECUTABLE_NAME)</string>
+	<key>CFBundleIdentifier</key>
+	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+	<key>CFBundleInfoDictionaryVersion</key>
+	<string>6.0</string>
+	<key>CFBundleName</key>
+	<string>ios_example</string>
+	<key>CFBundlePackageType</key>
+	<string>APPL</string>
+	<key>CFBundleShortVersionString</key>
+	<string>$(FLUTTER_BUILD_NAME)</string>
+	<key>CFBundleSignature</key>
+	<string>????</string>
+	<key>CFBundleVersion</key>
+	<string>$(FLUTTER_BUILD_NUMBER)</string>
+	<key>LSRequiresIPhoneOS</key>
+	<true/>
+	<key>UILaunchStoryboardName</key>
+	<string>LaunchScreen</string>
+	<key>UIMainStoryboardFile</key>
+	<string>Main</string>
+	<key>UISupportedInterfaceOrientations</key>
+	<array>
+		<string>UIInterfaceOrientationPortrait</string>
+		<string>UIInterfaceOrientationLandscapeLeft</string>
+		<string>UIInterfaceOrientationLandscapeRight</string>
+	</array>
+	<key>UISupportedInterfaceOrientations~ipad</key>
+	<array>
+		<string>UIInterfaceOrientationPortrait</string>
+		<string>UIInterfaceOrientationPortraitUpsideDown</string>
+		<string>UIInterfaceOrientationLandscapeLeft</string>
+		<string>UIInterfaceOrientationLandscapeRight</string>
+	</array>
+	<key>UIViewControllerBasedStatusBarAppearance</key>
+	<false/>
+</dict>
+</plist>

dev/integration_tests/codegen/ios/Runner/main.m

+#import <Flutter/Flutter.h>
+#import <UIKit/UIKit.h>
+#import "AppDelegate.h"
+
+int main(int argc, char* argv[]) {
+  @autoreleasepool {
+    return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
+  }
+}

packages/flutter_tools/lib/src/build_runner/build_runner.dart

@@ -29,11 +29,6 @@ import 'build_script_generator.dart';
 /// The minimum version of build_runner we can support in the flutter tool.
 const String kMinimumBuildRunnerVersion = '1.2.8';
 
-// Arbitrarily choosen multi-root file scheme. This is used to configure the
-// frontend_server to resolve a package uri to multiple filesystem directories.
-// In this case, the source directory and a generated directory.
-const String _kMultirootScheme = 'org-dartlang-app';
-
 /// A wrapper for a build_runner process which delegates to a generated
 /// build script.
 ///
@@ -170,7 +165,7 @@ class BuildRunner extends CodeGenerator {
   void _generatePackages(FlutterProject flutterProject) {
     final String oldPackagesContents = fs.file(PackageMap.globalPackagesPath).readAsStringSync();
     final String appName = flutterProject.manifest.appName;
-    final String newPackagesContents = oldPackagesContents.replaceFirst('$appName:lib/', '$appName:$_kMultirootScheme:/');
+    final String newPackagesContents = oldPackagesContents.replaceFirst('$appName:lib/', '$appName:$kMultiRootScheme:/');
     final String generatedPackagesPath = fs.path.setExtension(PackageMap.globalPackagesPath, '.generated');
     fs.file(generatedPackagesPath).writeAsStringSync(newPackagesContents);
   }

packages/flutter_tools/lib/src/codegen.dart

@@ -14,7 +14,10 @@ import 'dart/package_map.dart';
 import 'globals.dart';
 import 'project.dart';
 
-const String _kMultiRootScheme = 'org-dartlang-app';
+// Arbitrarily choosen multi-root file scheme. This is used to configure the
+// frontend_server to resolve a package uri to multiple filesystem directories.
+// In this case, the source directory and a generated directory.
+const String kMultiRootScheme = 'org-dartlang-app';
 
 /// The [CodeGenerator] instance.
 ///
@@ -109,6 +112,7 @@ class CodeGeneratingKernelCompiler implements KernelCompiler {
     String fileSystemScheme,
     String depFilePath,
     TargetModel targetModel = TargetModel.flutter,
+    String initializeFromDill,
   }) async {
     if (fileSystemRoots != null || fileSystemScheme != null || depFilePath != null || targetModel != null || sdkRoot != null || packagesPath != null) {
       printTrace('fileSystemRoots, fileSystemScheme, depFilePath, targetModel,'
@@ -141,9 +145,11 @@ class CodeGeneratingKernelCompiler implements KernelCompiler {
         fs.path.join(flutterProject.generated.path, 'lib${platform.pathSeparator}'),
         fs.path.join(flutterProject.directory.path, 'lib${platform.pathSeparator}'),
       ],
-      fileSystemScheme: _kMultiRootScheme,
+      fileSystemScheme: kMultiRootScheme,
       depFilePath: depFilePath,
       targetModel: targetModel,
+      // Pass an invalid file name to prevent frontend_server from initializing from dill.
+      initializeFromDill: ' ',
     );
   }
 }
@@ -179,10 +185,11 @@ class CodeGeneratingResidentCompiler implements ResidentCompiler {
         fs.path.join(flutterProject.generated.path, 'lib${platform.pathSeparator}'),
         fs.path.join(flutterProject.directory.path, 'lib${platform.pathSeparator}'),
       ],
-      fileSystemScheme: _kMultiRootScheme,
+      fileSystemScheme: kMultiRootScheme,
       targetModel: TargetModel.flutter,
       unsafePackageSerialization: unsafePackageSerialization,
-      initializeFromDill: initializeFromDill,
+      // Pass an invalid file name to prevent frontend_server from initializing from dill.
+      initializeFromDill: ' ',
     );
     return CodeGeneratingResidentCompiler._(residentCompiler, codegenDaemon);
   }
@@ -210,12 +217,6 @@ class CodeGeneratingResidentCompiler implements ResidentCompiler {
     if (_codegenDaemon.lastStatus == CodegenStatus.Failed) {
       printError('Codegeneration failed, halting build.');
     }
-    // Delete this file so that the frontend_server can handle multi-root.
-    // TODO(jonahwilliams): investigate frontend_server behavior in the presence
-    // of multi-root and initialize from dill.
-    if (outputPath != null && fs.file(outputPath).existsSync()) {
-      fs.file(outputPath).deleteSync();
-    }
     return _residentCompiler.recompile(
       mainPath,
       invalidatedFiles,

packages/flutter_tools/lib/src/compile.dart

@@ -175,6 +175,7 @@ class KernelCompiler {
     List<String> fileSystemRoots,
     String fileSystemScheme,
     bool targetProductVm = false,
+    String initializeFromDill,
   }) async {
     final String frontendServer = artifacts.getArtifactPath(
       Artifact.frontendServerSnapshotForEngineDartSdk
@@ -251,6 +252,9 @@ class KernelCompiler {
     if (fileSystemScheme != null) {
       command.addAll(<String>['--filesystem-scheme', fileSystemScheme]);
     }
+    if (initializeFromDill != null) {
+      command.addAll(<String>['--initialize-from-dill', initializeFromDill]);
+    }
 
     if (extraFrontEndOptions != null)
       command.addAll(extraFrontEndOptions);