Remove RenderViewHost parameter from WebContentsObserver::Did{Start|Stop}Loading.

extensions/browser/extension_host.cc

Index: extensions/browser/extension_host.cc
diff --git a/extensions/browser/extension_host.cc b/extensions/browser/extension_host.cc
index df9248912921d0c31a5ec790b4cf799e5f92d465..a18b0012522abfc3b767794fd65e969803c35533 100644
--- a/extensions/browser/extension_host.cc
+++ b/extensions/browser/extension_host.cc
@@ -267,13 +267,13 @@ void ExtensionHost::RenderProcessGone(base::TerminationStatus status) {
       content::Details<ExtensionHost>(this));
 }
 
-void ExtensionHost::DidStartLoading(content::RenderViewHost* render_view_host) {
+void ExtensionHost::DidStartLoading() {
   FOR_EACH_OBSERVER(DeferredStartRenderHostObserver,
                     deferred_start_render_host_observer_list_,
                     OnDeferredStartRenderHostDidStartLoading(this));
 }
 
-void ExtensionHost::DidStopLoading(content::RenderViewHost* render_view_host) {
+void ExtensionHost::DidStopLoading() {
   // Only record UMA for the first load. Subsequent loads will likely behave
   // quite different, and it's first load we're most interested in.
   if (!has_loaded_once_)