Report errors and warnings for hiding elements, issue 572.

compiler/java/com/google/dart/compiler/resolver/ClassScope.java

Index: compiler/java/com/google/dart/compiler/resolver/ClassScope.java
diff --git a/compiler/java/com/google/dart/compiler/resolver/ClassScope.java b/compiler/java/com/google/dart/compiler/resolver/ClassScope.java
index cba91e156ffed5e154b25c5edaea2de403a51a4e..2bf6ad4a63d7ecfb760054126c3a8a2051d83f56 100644
--- a/compiler/java/com/google/dart/compiler/resolver/ClassScope.java
+++ b/compiler/java/com/google/dart/compiler/resolver/ClassScope.java
@@ -34,6 +34,9 @@ class ClassScope extends Scope {
       ClassScope scope = new ClassScope(superclass.getElement(),
                                         new Scope("library", (LibraryElement) enclosing));
       element = scope.findElement(inLibrary, name);
+      if (element instanceof TypeVariableElement) {

[zundel, 2011/12/19 16:29:14]

just a thought: you could merge these two if blocks together into a single
switch.  I only prefer it in case the logic needs to be updated, its sometimes
easier to figure out the switch statement that lots of ifs.

switch (ElementKind.of(element)){
  case TYPE_VARIABLE:
    return null;
  case NONE: 
    break;
  default:
    return element;
}
  

[scheglov, 2011/12/19 19:10:38]

Done.

+        return null;
+      }
       if (element != null) {
         return element;
       }