ResourceScheduler should use renderer notifications instead of MRUCache to track renderers.

content/public/test/mock_render_process_host.cc

Index: content/public/test/mock_render_process_host.cc
diff --git a/content/public/test/mock_render_process_host.cc b/content/public/test/mock_render_process_host.cc
index a9e84e4c656ad694109087ce9cb97d3093e649ce..d877d443356d23767f3543f21449683845557195 100644
--- a/content/public/test/mock_render_process_host.cc
+++ b/content/public/test/mock_render_process_host.cc
@@ -52,9 +52,6 @@ int MockRenderProcessHost::GetNextRoutingID() {
   return ++prev_routing_id;
 }
 
-void MockRenderProcessHost::CancelResourceRequests(int render_widget_id) {
-}
-
 void MockRenderProcessHost::SimulateSwapOutACK(
     const ViewMsg_SwapOut_Params& params) {
 }