dart2js: Rename metadataEmitter to metadataCollector and make it independent of old emitter.

pkg/compiler/lib/src/js_emitter/type_test_generator.dart

Index: pkg/compiler/lib/src/js_emitter/type_test_generator.dart
diff --git a/pkg/compiler/lib/src/js_emitter/type_test_generator.dart b/pkg/compiler/lib/src/js_emitter/type_test_generator.dart
index cb9f879c32df96fbc6a06528825c2cec8de8a62c..bb2b0b9a059a90ff08fdd48a364ea5eb0960b56e 100644
--- a/pkg/compiler/lib/src/js_emitter/type_test_generator.dart
+++ b/pkg/compiler/lib/src/js_emitter/type_test_generator.dart
@@ -85,7 +85,8 @@ class TypeTestGenerator {
       }
 
       if (storeFunctionTypeInMetadata && !type.containsTypeVariables) {
-        result.functionTypeIndex = emitterTask.metadataEmitter.reifyType(type);
+        result.functionTypeIndex =
+            emitterTask.metadataCollector.reifyType(type);
       } else {
         RuntimeTypes rti = backend.rti;
         jsAst.Expression encoding = rti.getSignatureEncoding(type, thisAccess);