Migrate HostZoomMap to live in StoragePartition.

content/browser/loader/async_resource_handler.cc

Index: content/browser/loader/async_resource_handler.cc
diff --git a/content/browser/loader/async_resource_handler.cc b/content/browser/loader/async_resource_handler.cc
index 5125bec8607b43c930f76c1b31d229474f2a57f1..65254346443fe99e1628a451a4d048740641e8de 100644
--- a/content/browser/loader/async_resource_handler.cc
+++ b/content/browser/loader/async_resource_handler.cc
@@ -24,7 +24,9 @@
 #include "content/browser/resource_context_impl.h"
 #include "content/common/resource_messages.h"
 #include "content/common/view_messages.h"
+#include "content/public/browser/render_process_host.h"
 #include "content/public/browser/resource_dispatcher_host_delegate.h"
+#include "content/public/browser/storage_partition.h"
 #include "content/public/common/resource_response.h"
 #include "net/base/io_buffer.h"
 #include "net/base/load_flags.h"
@@ -193,8 +195,7 @@ bool AsyncResourceHandler::OnResponseStarted(ResourceResponse* response,
 
   DevToolsNetLogObserver::PopulateResponseInfo(request(), response);
 
-  HostZoomMap* host_zoom_map =
-      GetHostZoomMapForResourceContext(info->GetContext());
+  HostZoomMap* host_zoom_map = info->filter()->GetHostZoomMap();
 
   if (info->GetResourceType() == RESOURCE_TYPE_MAIN_FRAME && host_zoom_map) {
     const GURL& request_url = request()->url();