Cleanup application startup on Android devices (#6949)

- [x] Stop unnecessarily building the flx a second time on startup.
- [x] Stop unncessarily copying the flx to the device a second time on startup.
- [x] Remove `startBundle` and move logic into `startApp`.

packages/flutter_tools/lib/src/android/android_device.dart

@@ -13,7 +13,6 @@ import '../base/logger.dart';
 import '../base/process.dart';
 import '../build_info.dart';
 import '../device.dart';
-import '../flx.dart' as flx;
 import '../globals.dart';
 import '../protocol_discovery.dart';
 import 'adb.dart';
@@ -22,10 +21,6 @@ import 'android_sdk.dart';
 
 const String _defaultAdbPath = 'adb';
 
-// Path where the FLX bundle will be copied on the device.
-const String _deviceBundlePath = '/data/local/tmp/dev.flx';
-
-
 class AndroidDevices extends PollingDeviceDiscovery {
   AndroidDevices() : super('AndroidDevices');
 
@@ -274,60 +269,49 @@ class AndroidDevice extends Device {
     return null;
   }
 
-  Future<LaunchResult> startBundle(AndroidApk apk, String bundlePath, {
-    bool traceStartup: false,
+  @override
+  Future<LaunchResult> startApp(
+    ApplicationPackage package,
+    BuildMode mode, {
+    String mainPath,
     String route,
-    DebuggingOptions options
+    DebuggingOptions debuggingOptions,
+    Map<String, dynamic> platformArgs,
+    bool prebuiltApplication: false
   }) async {
-    printTrace('$this startBundle');
-
-    if (bundlePath != null) {
-      if (!FileSystemEntity.isFileSync(bundlePath)) {
-        printError('Cannot find $bundlePath');
+    if (!_checkForSupportedAdbVersion() || !_checkForSupportedAndroidVersion())
       return new LaunchResult.failed();
-      }
 
-      runCheckedSync(
-          adbCommandForDevice(<String>['push', bundlePath, _deviceBundlePath]));
-    }
+    final bool traceStartup = platformArgs['trace-startup'] ?? false;
+    final AndroidApk apk = package;
+    printTrace('$this startApp');
 
     ProtocolDiscovery observatoryDiscovery;
     ProtocolDiscovery diagnosticDiscovery;
 
     DeviceLogReader logReader = getLogReader();
-    if (options.debuggingEnabled) {
+    if (debuggingOptions.debuggingEnabled) {
       observatoryDiscovery = new ProtocolDiscovery(logReader, ProtocolDiscovery.kObservatoryService);
       diagnosticDiscovery = new ProtocolDiscovery(logReader, ProtocolDiscovery.kDiagnosticService);
     }
 
     List<String> cmd;
 
-    if (bundlePath != null) {
-      // Specify in the RUN intent the path to the local bundle pushed.
     cmd = adbCommandForDevice(<String>[
       'shell', 'am', 'start',
       '-a', 'android.intent.action.RUN',
-        '-d', _deviceBundlePath,
       '-f', '0x20000000',  // FLAG_ACTIVITY_SINGLE_TOP
       '--ez', 'enable-background-compilation', 'true',
     ]);
-    } else {
-      cmd = adbCommandForDevice(<String>[
-        'shell', 'am', 'start',
-        '-a', 'android.intent.action.RUN',
-        '-f', '0x20000000',  // FLAG_ACTIVITY_SINGLE_TOP
-        '--ez', 'enable-background-compilation', 'true',
-      ]);
-    }
 
     if (traceStartup)
       cmd.addAll(<String>['--ez', 'trace-startup', 'true']);
     if (route != null)
       cmd.addAll(<String>['--es', 'route', route]);
-    if (options.debuggingEnabled) {
-      if (options.buildMode == BuildMode.debug)
+    if (debuggingOptions.debuggingEnabled) {
+      if (debuggingOptions.buildMode == BuildMode.debug)
         cmd.addAll(<String>['--ez', 'enable-checked-mode', 'true']);
-      if (options.startPaused)
+      if (debuggingOptions.startPaused)
         cmd.addAll(<String>['--ez', 'start-paused', 'true']);
     }
     cmd.add(apk.launchActivity);
@@ -338,7 +322,7 @@ class AndroidDevice extends Device {
       return new LaunchResult.failed();
     }
 
-    if (!options.debuggingEnabled) {
+    if (!debuggingOptions.debuggingEnabled) {
       return new LaunchResult.succeeded();
     } else {
       // Wait for the service protocol port here. This will complete once the
@@ -348,7 +332,7 @@ class AndroidDevice extends Device {
       try {
         int observatoryDevicePort, diagnosticDevicePort;
 
-        if (options.buildMode == BuildMode.debug) {
+        if (debuggingOptions.buildMode == BuildMode.debug) {
           Future<List<int>> scrapeServicePorts = Future.wait(
               <Future<int>>[observatoryDiscovery.nextPort(), diagnosticDiscovery.nextPort()]
           );
@@ -360,7 +344,7 @@ class AndroidDevice extends Device {
         }
 
         printTrace('observatory port on device: $observatoryDevicePort');
-        int observatoryLocalPort = await options.findBestObservatoryPort();
+        int observatoryLocalPort = await debuggingOptions.findBestObservatoryPort();
         // TODO(devoncarew): Remember the forwarding information (so we can later remove the
         // port forwarding).
         observatoryLocalPort = await _forwardPort(ProtocolDiscovery.kObservatoryService, observatoryDevicePort, observatoryLocalPort);
@@ -368,7 +352,7 @@ class AndroidDevice extends Device {
         int diagnosticLocalPort;
         if (diagnosticDevicePort != null) {
           printTrace('diagnostic port on device: $diagnosticDevicePort');
-          diagnosticLocalPort = await options.findBestDiagnosticPort();
+          diagnosticLocalPort = await debuggingOptions.findBestDiagnosticPort();
           diagnosticLocalPort = await _forwardPort(ProtocolDiscovery.kDiagnosticService, diagnosticDevicePort, diagnosticLocalPort);
         }
 
@@ -389,42 +373,6 @@ class AndroidDevice extends Device {
     }
   }
 
-  @override
-  Future<LaunchResult> startApp(
-    ApplicationPackage package,
-    BuildMode mode, {
-    String mainPath,
-    String route,
-    DebuggingOptions debuggingOptions,
-    Map<String, dynamic> platformArgs,
-    bool prebuiltApplication: false
-  }) async {
-    if (!_checkForSupportedAdbVersion() || !_checkForSupportedAndroidVersion())
-      return new LaunchResult.failed();
-
-    String localBundlePath;
-
-    if (!prebuiltApplication) {
-      localBundlePath = await flx.buildFlx(
-        mainPath: mainPath,
-        precompiledSnapshot: isAotBuildMode(debuggingOptions.buildMode),
-        includeRobotoFonts: false
-      );
-      if (localBundlePath == null)
-        return new LaunchResult.failed();
-    }
-
-    printTrace('Starting bundle for $this.');
-
-    return startBundle(
-      package,
-      localBundlePath,
-      traceStartup: platformArgs['trace-startup'] ?? false,
-      route: route,
-      options: debuggingOptions
-    );
-  }
-
   @override
   bool get supportsHotMode => true;