Revert type hierarchy changes

tests/standalone/typed_data_test.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 // Dart test program for testing typed data.
 
 // VMOptions=--optimization_counter_threshold=10
 
 // Library tag to be able to run in html test framework.
 library TypedDataTest;
@@ skipping 14 matching lines @@
   for (int i = 0; i < 10; i++) {
     Expect.equals(0, typed_data[i]);
   }
 }
 
 void testCreateClampedUint8TypedData() {
   Uint8ClampedList typed_data;
 
   typed_data = new Uint8ClampedList(0);
   Expect.isTrue(typed_data is Uint8ClampedList);
-  Expect.isFalse(typed_data is Uint8List);
+  Expect.isTrue(typed_data is Uint8List);
   Expect.equals(0, typed_data.length);
   Expect.equals(0, typed_data.lengthInBytes);
 
   typed_data = new Uint8ClampedList(10);
   Expect.equals(10, typed_data.length);
   for (int i = 0; i < 10; i++) {
     Expect.equals(0, typed_data[i]);
   }
 }
 
@@ skipping 325 matching lines @@
     testSetAtIndex(float64list, 1.4260258159703532e-105, true);
     testGetAtIndex(float64list, 1.4260258159703532e-105);
   }
   testTypedDataRange(true);
   testUnsignedTypedDataRange(true);
   testViewCreation();
   testWhere();
   testCreationFromList();
 }