Fix a few warnings (unused imports, missing return).

lib/core/scope.dart

@@ -238,6 +238,7 @@ class Scope {
       assert(locals == null);
       if (expression is EvalFunction1) return expression(context);
       if (expression is EvalFunction0) return expression();
+      return null;
     }
   }
 

lib/core_dom/module.dart

@@ -10,7 +10,6 @@ import 'package:perf_api/perf_api.dart';
 
 import 'package:angular/core/module.dart';
 import 'package:angular/core/parser/parser.dart';
-import 'package:angular/utils.dart';
 
 part 'block.dart';
 part 'block_factory.dart';

lib/tools/source_metadata_extractor.dart

@@ -4,7 +4,6 @@ import 'package:analyzer/src/generated/ast.dart';
 
 import 'package:angular/tools/source_crawler.dart';
 import 'package:angular/tools/common.dart';
-import 'package:angular/utils.dart';
 
 const String _COMPONENT = '-component';
 const String _DIRECTIVE = '-directive';

run-test.sh

@@ -2,7 +2,7 @@
 
 set -e
 
-export DART_SDK=`which dart | sed -e 's/\/dart\-sdk\/.*$/\/dart-sdk/'`
+# export DART_SDK=`which dart | sed -e 's/\/dart\-sdk\/.*$/\/dart-sdk/'`
 
 # OS-specific Dartium path defaults
 case $( uname -s ) in