Add new extension APIs related to animation policy.

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 9614814d1a2232c9a4de57e2ea6bc8ddf9385c15..be5e0a74733645a391215b697766fe98b3924453 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -698,6 +698,11 @@ void WebContentsImpl::ClearNavigationTransitionData() {
   node->render_manager()->ClearNavigationTransitionData();
 }
 
+void WebContentsImpl::SetImageAnimationPolicy(const std::string& policy) {
+  if (GetRenderViewHost())
+    GetRenderViewHostImpl()->OnWebkitPreferencesChanged();
+}
+
 WebUI* WebContentsImpl::CreateWebUI(const GURL& url) {
   WebUIImpl* web_ui = new WebUIImpl(this);
   WebUIController* controller = WebUIControllerFactoryRegistry::GetInstance()->