Remove a chrome dependency by removing Prerender from ResourceDispatcherHost.

chrome/browser/prerender/prerender_contents.cc

Index: chrome/browser/prerender/prerender_contents.cc
diff --git a/chrome/browser/prerender/prerender_contents.cc b/chrome/browser/prerender/prerender_contents.cc
index ac050f17af16212f4603296080fb1fd4164af869..ade0457bfb879722ad3f032690264829f9f9f2bd 100644
--- a/chrome/browser/prerender/prerender_contents.cc
+++ b/chrome/browser/prerender/prerender_contents.cc
@@ -31,6 +31,7 @@
 #include "content/browser/renderer_host/render_view_host.h"
 #include "content/browser/renderer_host/resource_dispatcher_host.h"
 #include "content/browser/renderer_host/resource_request_details.h"
+#include "content/browser/resource_context.h"
 #include "content/browser/site_instance.h"
 #include "content/browser/tab_contents/tab_contents_delegate.h"
 #include "content/browser/tab_contents/tab_contents_view.h"
@@ -186,8 +187,10 @@ void PrerenderContents::StartPrerenderingOld(
   // Register this with the PrerenderTracker as a prerendering RenderViewHost.
   // This must be done before the Navigate message to catch all resource
   // requests.
-  PrerenderTracker::GetInstance()->OnPrerenderingStarted(child_id_, route_id_,
-                                                         prerender_manager_);
+  g_browser_process->prerender_tracker()->OnPrerenderingStarted(

[cbentzel, 2011/05/24 11:37:19]

Would it make more sense to pass the PrerenderTracker* into the PrerenderManager
[and in turn the PrerenderContents object]

[dominich, 2011/05/24 15:10:28]

I prefer to be explicit about where this is coming from rather than muddy the
waters of ownership. The lookup here is very low cost compared to the other
processing we're doing and it makes it obvious that we're calling out to
something global.

[cbentzel, 2011/05/24 15:13:25]

I wasn't worried about performance, just dislike reaching out to the global
instead of passing in the dependency.

[jam, 2011/05/24 16:06:24]

I don't think this makes ownership murky.  It's a very common pattern that we
give objects on creation the other objects that they might need.  Otherwise
BrowserProcess will explode with a list of getters.

[dominich, 2011/05/24 16:54:21]

Done.

+      child_id_,
+      route_id_,
+      prerender_manager_);
 
   // Close ourselves when the application is shutting down.
   notification_registrar_.Add(this, NotificationType::APP_TERMINATING,
@@ -290,8 +293,10 @@ void PrerenderContents::StartPrerendering(
   // RenderViewHost. This must be done before the Navigate message to catch all
   // resource requests, but as it is on the same thread as the Navigate message
   // (IO) there is no race condition.
-  PrerenderTracker::GetInstance()->OnPrerenderingStarted(child_id_, route_id_,
-                                                         prerender_manager_);
+  g_browser_process->prerender_tracker()->OnPrerenderingStarted(
+      child_id_,
+      route_id_,
+      prerender_manager_);
 
   // Close ourselves when the application is shutting down.
   notification_registrar_.Add(this, NotificationType::APP_TERMINATING,
@@ -377,7 +382,7 @@ PrerenderContents::~PrerenderContents() {
     render_view_host_->Shutdown();
 
   if (child_id_ != -1 && route_id_ != -1) {
-    PrerenderTracker::GetInstance()->OnPrerenderingFinished(
+    g_browser_process->prerender_tracker()->OnPrerenderingFinished(
         child_id_, route_id_);
   }
 
@@ -720,15 +725,14 @@ void PrerenderContents::Destroy(FinalStatus final_status) {
     // because destroy may be called directly from the UI thread without calling
     // TryCancel().  This is difficult to completely avoid, since prerendering
     // can be cancelled before a RenderView is created.
-    bool is_cancelled =
-        PrerenderTracker::GetInstance()->TryCancel(child_id_, route_id_,
-                                                   final_status);
+    bool is_cancelled = g_browser_process->prerender_tracker()->TryCancel(
+        child_id_, route_id_, final_status);
     CHECK(is_cancelled);
 
     // A different final status may have been set already from another thread.
     // If so, use it instead.
-    if (!PrerenderTracker::GetInstance()->GetFinalStatus(child_id_, route_id_,
-                                                         &final_status)) {
+    if (!g_browser_process->prerender_tracker()->GetFinalStatus(
+            child_id_, route_id_, &final_status)) {
       NOTREACHED();
     }
   }