Remove most prerendering code/references from content.

The only place where prerendering code remains in content 
is in ResourceDispatcherHost. 

As NavigationState can no longer be used to track 
prerendering histogram information, the prerendering 
renderer-side histograms have been reworked (And 
renamed) as well. 

The histogram intended to track use of 
prerendering RenderViews has been removed, as 
histograms are not recorded when a RenderView is 
destroyed. 

BUG=77090
TEST=Compiles, existing PrerenderBrowserTests, grep

Review URL: http://codereview.chromium.org/6900026

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@83642 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 17 insertions, 5 deletions

diff --git a/chrome/renderer/blocked_plugin.cc b/chrome/renderer/blocked_plugin.cc
index 6917f21..a1a1897 100644
--- a/chrome/renderer/blocked_plugin.cc
+++ b/chrome/renderer/blocked_plugin.cc
@@ -150,11 +150,11 @@ bool BlockedPlugin::OnMessageReceived(const IPC::Message& message) {
       gLastActiveMenu == this) {
     ViewMsg_CustomContextMenuAction::Dispatch(
         &message, this, this, &BlockedPlugin::OnMenuItemSelected);
-  } else if (message.type() == ViewMsg_LoadBlockedPlugins::ID) {
-    LoadPlugin();
-  } else if (message.type() == ViewMsg_DisplayPrerenderedPage::ID) {
-    if (is_blocked_for_prerendering_)
-      LoadPlugin();
+  } else {
+    IPC_BEGIN_MESSAGE_MAP(BlockedPlugin, message)
+      IPC_MESSAGE_HANDLER(ViewMsg_LoadBlockedPlugins, OnLoadBlockedPlugins)
+      IPC_MESSAGE_HANDLER(ViewMsg_SetIsPrerendering, OnSetIsPrerendering)
+    IPC_END_MESSAGE_MAP()
   }
 
   return false;
@@ -170,6 +170,18 @@ void BlockedPlugin::OnMenuItemSelected(
   }
 }
 
+void BlockedPlugin::OnLoadBlockedPlugins() {
+  LoadPlugin();
+}
+
+void BlockedPlugin::OnSetIsPrerendering(bool is_prerendering) {
+  // Prerendering can only be enabled prior to a RenderView's first navigation,
+  // so no BlockedPlugin should see the notification that enables prerendering.
+  DCHECK(!is_prerendering);
+  if (!is_prerendering)
+    LoadPlugin();
+}
+
 void BlockedPlugin::LoadPlugin() {
   CHECK(plugin_);
   // This is not strictly necessary but is an important defense in case the