Have MemberMap backed by a HashMap, not an array

editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/verifier/ErrorVerifier.java

Index: editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/verifier/ErrorVerifier.java
diff --git a/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/verifier/ErrorVerifier.java b/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/verifier/ErrorVerifier.java
index b03e9f4db4de4939626004a775e0e82db2e38b64..00c9e555e94bce477507b93ee4bd0deaf6f3560f 100644
--- a/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/verifier/ErrorVerifier.java
+++ b/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/verifier/ErrorVerifier.java
@@ -4114,9 +4114,9 @@ public class ErrorVerifier extends RecursiveAstVisitor<Void> {
     //
     MemberMap membersInheritedFromInterfaces = inheritanceManager.getMapOfMembersInheritedFromInterfaces(enclosingClass);
     MemberMap membersInheritedFromSuperclasses = inheritanceManager.getMapOfMembersInheritedFromClasses(enclosingClass);
-    for (int i = 0; i < membersInheritedFromInterfaces.getSize(); i++) {
-      String memberName = membersInheritedFromInterfaces.getKey(i);
-      ExecutableElement executableElt = membersInheritedFromInterfaces.getValue(i);
+    Set<String> keys = membersInheritedFromInterfaces.getKeys();
+    for (String memberName : keys) {
+      ExecutableElement executableElt = membersInheritedFromInterfaces.getValue(memberName);
       if (memberName == null) {
         break;
       }