Retain fewer names for reflection.

dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart

Index: dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart
diff --git a/dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart b/dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart
index 2302aec5576d8b4dd92cbe738a3cf234332b6724..a0ba6b43316c6002207ef433df78fcaa4843125a 100644
--- a/dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart
+++ b/dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart
@@ -1289,7 +1289,15 @@ class CodeEmitterTask extends CompilerTask {
   }
 
   String getReflectionName(elementOrSelector, String mangledName) {

[Johnni Winther, 2013/08/07 10:47:34]

Add documentation to this method.

[ahe, 2013/08/07 14:03:17]

Done.

-    if (!backend.retainName(elementOrSelector.name)) return null;
+    SourceString name = elementOrSelector.name;
+    if (!backend.retainName(name)) {
+      if (name == const SourceString('') && elementOrSelector is Element) {
+        // Make sure to retain names of unnamed constructors.
+        if (!backend.isNeededForReflection(elementOrSelector)) return null;
+      } else {
+        return null;
+      }
+    }
     // TODO(ahe): Enable the next line when I can tell the difference between
     // an instance method and a global.  They may have the same mangled name.
     // if (recordedMangledNames.contains(mangledName)) return null;
@@ -1961,6 +1969,7 @@ class CodeEmitterTask extends CompilerTask {
     buffer.write(jsAst.prettyPrint(builder.toObjectInitializer(), compiler));
     if (backend.retainName(classElement.name)) {
       buffer.write(',$n$n"+${classElement.name.slowToString()}": 0');
+      recordedMangledNames.add(className);
     }
   }