TextureLayer: clear texture id when clearing client

cc/layers/texture_layer.cc

Index: cc/layers/texture_layer.cc
diff --git a/cc/layers/texture_layer.cc b/cc/layers/texture_layer.cc
index acabc87f91410a0ca0537760df60e88908d6679d..eb62c0d94d3fa9526a7ba63f09f6828fb6c8968c 100644
--- a/cc/layers/texture_layer.cc
+++ b/cc/layers/texture_layer.cc
@@ -64,6 +64,11 @@ TextureLayer::~TextureLayer() {
     texture_mailbox_.RunReleaseCallback(texture_mailbox_.sync_point());
 }
 
+void TextureLayer::ClearClient() {
+  client_ = NULL;
+  SetTextureId(0);
+}
+
 scoped_ptr<LayerImpl> TextureLayer::CreateLayerImpl(LayerTreeImpl* tree_impl) {
   return TextureLayerImpl::Create(tree_impl, id(), uses_mailbox_).
       PassAs<LayerImpl>();