Fix await parsing.

tests/compiler/dart2js/mock_compiler.dart

Index: tests/compiler/dart2js/mock_compiler.dart
diff --git a/tests/compiler/dart2js/mock_compiler.dart b/tests/compiler/dart2js/mock_compiler.dart
index 2d40fc99dfa36f1c54fc8aa3b784150ac71b210b..177083d4f6844c74eeee956bebd95da2749dbb14 100644
--- a/tests/compiler/dart2js/mock_compiler.dart
+++ b/tests/compiler/dart2js/mock_compiler.dart
@@ -74,6 +74,7 @@ class MockCompiler extends Compiler {
        // affected by inlining support.
        bool disableInlining: true,
        bool trustTypeAnnotations: false,
+       bool enableAsyncAwait: false,
        int this.expectedWarnings,
        int this.expectedErrors,
        api.CompilerOutputProvider outputProvider,
@@ -91,7 +92,8 @@ class MockCompiler extends Compiler {
               preserveComments: preserveComments,
               trustTypeAnnotations: trustTypeAnnotations,
               showPackageWarnings: true,
-              outputProvider: outputProvider) {
+              outputProvider: outputProvider,
+              enableAsyncAwait: enableAsyncAwait) {
     this.disableInlining = disableInlining;
 
     deferredLoadTask = new MockDeferredLoadTask(this);