Move process-per-site logic from BrowsingInstance to RenderProcessHost.

content/test/mock_render_process_host.cc

Index: content/test/mock_render_process_host.cc
diff --git a/content/test/mock_render_process_host.cc b/content/test/mock_render_process_host.cc
index 31d94dbed722957f8c135749318a5875a6406276..0a40b9f0d4cd4fb221029a9c8ad6de7378d1fe0f 100644
--- a/content/test/mock_render_process_host.cc
+++ b/content/test/mock_render_process_host.cc
@@ -36,7 +36,7 @@ MockRenderProcessHost::~MockRenderProcessHost() {
   if (factory_)
     factory_->Remove(this);
   // In unit tests, Release() might not have been called.
-  RenderProcessHostImpl::UnregisterHost(GetID());
+  RenderProcessHostImpl::UnregisterHost(GetID(), this);
 }
 
 void MockRenderProcessHost::EnableSendQueue() {
@@ -165,7 +165,7 @@ void MockRenderProcessHost::Cleanup() {
         Source<RenderProcessHost>(this),
         NotificationService::NoDetails());
     MessageLoop::current()->DeleteSoon(FROM_HERE, this);
-    RenderProcessHostImpl::UnregisterHost(GetID());
+    RenderProcessHostImpl::UnregisterHost(GetID(), this);
   }
 }