Add forEachLibraryMember and forEachConstructor to ElementEnvironment

pkg/compiler/lib/src/resolution/resolution_strategy.dart

Index: pkg/compiler/lib/src/resolution/resolution_strategy.dart
diff --git a/pkg/compiler/lib/src/resolution/resolution_strategy.dart b/pkg/compiler/lib/src/resolution/resolution_strategy.dart
index a7125c7e123e463237c5a3ceec7a57e5e81c1296..f2647fe418ac4a188e5e0d515f8eef7c3ceb75dd 100644
--- a/pkg/compiler/lib/src/resolution/resolution_strategy.dart
+++ b/pkg/compiler/lib/src/resolution/resolution_strategy.dart
@@ -294,6 +294,7 @@ class _CompilerElementEnvironment implements ElementEnvironment {
       {bool required: false}) {
     cls.ensureResolved(_resolution);
     ConstructorElement constructor = cls.implementation.lookupConstructor(name);
+    // TODO(johnniwinther): Skip redirecting factories.
     if (constructor == null && required) {
       throw new SpannableAssertionFailure(
           cls,
@@ -316,6 +317,17 @@ class _CompilerElementEnvironment implements ElementEnvironment {
   }
 
   @override
+  void forEachConstructor(
+      ClassElement cls, void f(ConstructorEntity constructor)) {
+    cls.ensureResolved(_resolution);
+    for (ConstructorElement constructor in cls.implementation.constructors) {
+      _resolution.ensureResolved(constructor.declaration);
+      if (constructor.isRedirectingFactory) continue;
+      f(constructor);
+    }
+  }
+
+  @override
   ClassEntity getSuperClass(ClassElement cls,
       {bool skipUnnamedMixinApplications: false}) {
     cls.ensureResolved(_resolution);
@@ -373,6 +385,17 @@ class _CompilerElementEnvironment implements ElementEnvironment {
   }
 
   @override
+  void forEachLibraryMember(
+      LibraryElement library, void f(MemberEntity member)) {
+    library.implementation.forEachLocalMember((Element element) {
+      if (!element.isClass && !element.isTypedef) {
+        MemberElement member = element;
+        f(member);
+      }
+    });
+  }
+
+  @override
   ClassElement lookupClass(LibraryElement library, String name,
       {bool required: false}) {
     ClassElement cls = library.implementation.findLocal(name);