Revert "Always compile with isysroot on iOS to point to SDK root (#45436)" (#45555)

Analyzer warning.

packages/flutter_tools/lib/src/base/build.dart

@@ -242,16 +242,8 @@ class AOTSnapshotter {
 
     const String embedBitcodeArg = '-fembed-bitcode';
     final String assemblyO = fs.path.join(outputPath, 'snapshot_assembly.o');
-    List<String> isysrootArgs;
-    if (isIOS) {
-      final String iPhoneSDKLocation = await xcode.iPhoneSdkLocation();
-      if (iPhoneSDKLocation != null) {
-        isysrootArgs = <String>['-isysroot', iPhoneSDKLocation];
-      }
-    }
     final RunResult compileResult = await xcode.cc(<String>[
       '-arch', targetArch,
-      if (isysrootArgs != null) ...isysrootArgs,
       if (bitcode) embedBitcodeArg,
       '-c',
       assemblyPath,
@@ -273,7 +265,7 @@ class AOTSnapshotter {
       '-Xlinker', '-rpath', '-Xlinker', '@loader_path/Frameworks',
       '-install_name', '@rpath/App.framework/App',
       if (bitcode) embedBitcodeArg,
-      if (isysrootArgs != null) ...isysrootArgs,
+      if (bitcode && isIOS) ...<String>[embedBitcodeArg, '-isysroot', await xcode.iPhoneSdkLocation()],
       '-o', appLib,
       assemblyO,
     ];

packages/flutter_tools/test/general.shard/base/build_test.dart

@@ -214,7 +214,6 @@ void main() {
 
   group('Snapshotter - AOT', () {
     const String kSnapshotDart = 'snapshot.dart';
-    const String kSDKPath = '/path/to/sdk';
     String skyEnginePath;
 
     _FakeGenSnapshot genSnapshot;
@@ -244,8 +243,6 @@ void main() {
       mockAndroidSdk = MockAndroidSdk();
       mockArtifacts = MockArtifacts();
       mockXcode = MockXcode();
-      when(mockXcode.iPhoneSdkLocation()).thenAnswer((_) => Future<String>.value(kSDKPath));
-
       bufferLogger = BufferLogger();
       for (BuildMode mode in BuildMode.values) {
         when(mockArtifacts.getArtifactPath(Artifact.snapshotDart,
@@ -337,19 +334,8 @@ void main() {
         'main.dill',
       ]);
 
-      final VerificationResult toVerifyCC = verify(xcode.cc(captureAny));
-      expect(toVerifyCC.callCount, 1);
-      final List<String> ccArgs = toVerifyCC.captured.first;
-      expect(ccArgs, contains('-fembed-bitcode'));
-      expect(ccArgs, contains('-isysroot'));
-      expect(ccArgs, contains(kSDKPath));
-
-      final VerificationResult toVerifyClang = verify(xcode.clang(captureAny));
-      expect(toVerifyClang.callCount, 1);
-      final List<String> clangArgs = toVerifyClang.captured.first;
-      expect(clangArgs, contains('-fembed-bitcode'));
-      expect(clangArgs, contains('-isysroot'));
-      expect(clangArgs, contains(kSDKPath));
+      verify(xcode.cc(argThat(contains('-fembed-bitcode')))).called(1);
+      verify(xcode.clang(argThat(contains('-fembed-bitcode')))).called(1);
 
       final File assemblyFile = fs.file(assembly);
       expect(assemblyFile.existsSync(), true);
@@ -394,19 +380,8 @@ void main() {
         'main.dill',
       ]);
 
-      final VerificationResult toVerifyCC = verify(xcode.cc(captureAny));
-      expect(toVerifyCC.callCount, 1);
-      final List<String> ccArgs = toVerifyCC.captured.first;
-      expect(ccArgs, contains('-fembed-bitcode'));
-      expect(ccArgs, contains('-isysroot'));
-      expect(ccArgs, contains(kSDKPath));
-
-      final VerificationResult toVerifyClang = verify(xcode.clang(captureAny));
-      expect(toVerifyClang.callCount, 1);
-      final List<String> clangArgs = toVerifyClang.captured.first;
-      expect(clangArgs, contains('-fembed-bitcode'));
-      expect(clangArgs, contains('-isysroot'));
-      expect(clangArgs, contains(kSDKPath));
+      verify(xcode.cc(argThat(contains('-fembed-bitcode')))).called(1);
+      verify(xcode.clang(argThat(contains('-fembed-bitcode')))).called(1);
 
       final File assemblyFile = fs.file(assembly);
       final File assemblyBitcodeFile = fs.file('$assembly.stripped.S');
@@ -456,9 +431,6 @@ void main() {
       verifyNever(xcode.cc(argThat(contains('-fembed-bitcode'))));
       verifyNever(xcode.clang(argThat(contains('-fembed-bitcode'))));
 
-      verify(xcode.cc(argThat(contains('-isysroot')))).called(1);
-      verify(xcode.clang(argThat(contains('-isysroot')))).called(1);
-
       final File assemblyFile = fs.file(assembly);
       expect(assemblyFile.existsSync(), true);
       expect(assemblyFile.readAsStringSync().contains('.section __DWARF'), true);