Fix remaining cc files to compile with Clang

cc/CCHeadsUpDisplayLayerImpl.cpp

Index: cc/CCHeadsUpDisplayLayerImpl.cpp
diff --git a/cc/CCHeadsUpDisplayLayerImpl.cpp b/cc/CCHeadsUpDisplayLayerImpl.cpp
index 924219d1dba3f8f60ee9790ee9312beb352fc838..d6686724fe869ac694ee63c456f54ea5298f0edd 100644
--- a/cc/CCHeadsUpDisplayLayerImpl.cpp
+++ b/cc/CCHeadsUpDisplayLayerImpl.cpp
@@ -126,6 +126,11 @@ void CCHeadsUpDisplayLayerImpl::didLoseContext()
     m_hudTexture.clear();
 }
 
+bool CCHeadsUpDisplayLayerImpl::layerIsAlwaysDamaged() const
+{
+    return true;
+}
+
 void CCHeadsUpDisplayLayerImpl::drawHudContents(SkCanvas* canvas)
 {
     const CCLayerTreeSettings& settings = layerTreeHostImpl()->settings();
@@ -282,4 +287,9 @@ void CCHeadsUpDisplayLayerImpl::drawDebugRects(SkCanvas* canvas, CCDebugRectHist
     }
 }
 
+const char* CCHeadsUpDisplayLayerImpl::layerTypeAsString() const
+{
+    return "HeadsUpDisplayLayer";
+}
+
 }