| Index: pkg/compiler/lib/src/dart2js.dart
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| diff --git a/pkg/compiler/lib/src/dart2js.dart b/pkg/compiler/lib/src/dart2js.dart
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| index d034f3df1b4900d708641e003bad3c8e6500edde..e5a8f5cb99bf47975db0a521344d4391058286f5 100644
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| --- a/pkg/compiler/lib/src/dart2js.dart
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| +++ b/pkg/compiler/lib/src/dart2js.dart
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| @@ -116,6 +116,7 @@ Future compile(List<String> argv) {
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|    bool analyzeAll = false;
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|    bool enableAsyncAwait = false;
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|    bool trustTypeAnnotations = false;
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| +  bool trustPrimitives = false;
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|    bool checkedMode = false;
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|    // List of provided options that imply that output is expected.
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|    List<String> optionsImplyCompilation = <String>[];
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| @@ -210,6 +211,11 @@ Future compile(List<String> argv) {
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|      implyCompilation(argument);
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|    }
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|  
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| +  setTrustPrimitives(String argument) {
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| +    trustPrimitives = true;
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| +    implyCompilation(argument);
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| +  }
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| +
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|    setCheckedMode(String argument) {
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|      checkedMode = true;
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|      passThrough(argument);
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| @@ -309,6 +315,9 @@ Future compile(List<String> argv) {
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|      new OptionHandler('--trust-type-annotations',
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|                        (_) => setTrustTypeAnnotations(
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|                            '--trust-type-annotations')),
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| +    new OptionHandler('--trust-primitives',
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| +                      (_) => setTrustPrimitives(
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| +                          '--trust-primitives')),
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|      new OptionHandler(r'--help|/\?|/h', (_) => wantHelp = true),
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|      new OptionHandler('--package-root=.+|-p.+', setPackageRoot),
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|      new OptionHandler('--analyze-all', setAnalyzeAll),
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| 
 |