Fix CC*Renderer and CC*LayerImpl to compile with Clang

cc/CCVideoLayerImpl.cpp

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 
 #if USE(ACCELERATED_COMPOSITING)
 
 #include "CCVideoLayerImpl.h"
 
@@ skipping 363 matching lines @@
     layerTreeHostImpl()->setNeedsRedraw();
 }
 
 void CCVideoLayerImpl::dumpLayerProperties(std::string* str, int indent) const
 {
     str->append(indentString(indent));
     str->append("video layer\n");
     CCLayerImpl::dumpLayerProperties(str, indent);
 }
 
+const char* CCVideoLayerImpl::layerTypeAsString() const
+{
+    return "VideoLayer";
+}
+
 }
 
 #endif // USE(ACCELERATED_COMPOSITING)