cc: Disable partial updates when impl-side painting is used.

This prevents us from updating textures currently in use by active
tree before tree activation.

BUG=173886


Review URL: https://chromiumcodereview.appspot.com/12185008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@182218 0039d316-1c4b-4281-b951-d872f2087c98

cc/layer_tree_host.cc

@@ -157,7 +157,7 @@ void LayerTreeHost::initializeRenderer()
 
     // Update m_settings based on partial update capability.
     size_t maxPartialTextureUpdates = 0;
-    if (m_proxy->rendererCapabilities().allowPartialTextureUpdates)
+    if (m_proxy->rendererCapabilities().allowPartialTextureUpdates && !m_settings.implSidePainting)
         maxPartialTextureUpdates = std::min(m_settings.maxPartialTextureUpdates, m_proxy->maxPartialTextureUpdates());
     m_settings.maxPartialTextureUpdates = maxPartialTextureUpdates;