Revert "Add runtime_data.dart to the whitelist of files with unused members." and "Emit declaration…

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

Index: sdk/lib/_internal/compiler/implementation/js_backend/backend.dart
diff --git a/sdk/lib/_internal/compiler/implementation/js_backend/backend.dart b/sdk/lib/_internal/compiler/implementation/js_backend/backend.dart
index 9f19f3983283d49f2a8b119f3549e083a10383d5..dd9a80ca73d2606b22414a5a0d675100eeecb51e 100644
--- a/sdk/lib/_internal/compiler/implementation/js_backend/backend.dart
+++ b/sdk/lib/_internal/compiler/implementation/js_backend/backend.dart
@@ -300,6 +300,10 @@ class JavaScriptBackend extends Backend {
   /// List of elements that the backend may use.
   final Set<Element> helpersUsed = new Set<Element>();
 
+
+  /// Set of typedefs that are used as type literals.
+  final Set<TypedefElement> typedefTypeLiterals = new Set<TypedefElement>();
+
   /// All the checked mode helpers.
   static const checkedModeHelpers = CheckedModeHelper.helpers;
 
@@ -1960,7 +1964,7 @@ class JavaScriptionResolutionCallbacks extends ResolutionCallbacks {
     // when reflection is used.  However, as long as we disable tree-shaking
     // eagerly it doesn't matter.
     if (type.isTypedef) {
-      backend.compiler.world.allTypedefs.add(type.element);
+      backend.typedefTypeLiterals.add(type.element);
     }
     backend.customElementsAnalysis.registerTypeLiteral(type, registry);
   }