Finish strong mode cleaning of dart2js.

pkg/compiler/lib/src/js_backend/mirrors_data.dart

Index: pkg/compiler/lib/src/js_backend/mirrors_data.dart
diff --git a/pkg/compiler/lib/src/js_backend/mirrors_data.dart b/pkg/compiler/lib/src/js_backend/mirrors_data.dart
index 0ceaafcaca455f2462a7c57f581d40c8a42117c9..0b7319a4cf5e32b854f6a07c12d5fa6c5cdc2172 100644
--- a/pkg/compiler/lib/src/js_backend/mirrors_data.dart
+++ b/pkg/compiler/lib/src/js_backend/mirrors_data.dart
@@ -372,7 +372,7 @@ class MirrorsDataImpl implements MirrorsData, MirrorsDataBuilder {
       }
     }
     if (metaTargets != null) {
-      for (var element in metaTargets) {
+      for (dynamic element in metaTargets) {
         if (element is ClassEntity) {
           metaTargetsUsed.add(element);
         }
@@ -569,7 +569,8 @@ class MirrorsDataImpl implements MirrorsData, MirrorsDataBuilder {
         assert(cls.isResolved, failedAt(cls));
         _classesNeededForReflection.add(cls);
         // 2) its constructors (if resolved)
-        cls.constructors.forEach((ConstructorElement constructor) {
+        cls.constructors.forEach((Element _constructor) {
+          ConstructorElement constructor = _constructor;
           if (worldBuilder.isMemberUsed(constructor)) {
             _membersNeededForReflection.add(constructor);
           }
@@ -580,8 +581,8 @@ class MirrorsDataImpl implements MirrorsData, MirrorsDataBuilder {
           if (worldBuilder.isMemberUsed(element)) {
             memberNames.add(member.name);
             _membersNeededForReflection.add(element);
-            element.nestedClosures
-                .forEach((SynthesizedCallMethodElementX callFunction) {
+            element.nestedClosures.forEach((FunctionElement _callFunction) {
+              SynthesizedCallMethodElementX callFunction = _callFunction;
               _membersNeededForReflection.add(callFunction);
               _classesNeededForReflection.add(callFunction.closureClass);
             });
@@ -589,7 +590,8 @@ class MirrorsDataImpl implements MirrorsData, MirrorsDataBuilder {
         });
         // 4) all overriding members of subclasses/subtypes (should be resolved)
         if (closedWorld.hasAnyStrictSubtype(cls)) {
-          closedWorld.forEachStrictSubtypeOf(cls, (ClassElement subcls) {
+          closedWorld.forEachStrictSubtypeOf(cls, (ClassEntity _subcls) {
+            ClassElement subcls = _subcls;
             subcls.forEachClassMember((Member member) {
               if (memberNames.contains(member.name)) {
                 // TODO(20993): find out why this assertion fails.
@@ -610,7 +612,8 @@ class MirrorsDataImpl implements MirrorsData, MirrorsDataBuilder {
         }
       } else {
         // check members themselves
-        cls.constructors.forEach((ConstructorElement element) {
+        cls.constructors.forEach((Element _element) {
+          ConstructorElement element = _element;
           if (!worldBuilder.isMemberUsed(element)) return;
           if (_memberReferencedFromMirrorSystem(element)) {
             _membersNeededForReflection.add(element);