Consistently use LoFi for an entire page

content/public/browser/resource_dispatcher_host_delegate.h

Index: content/public/browser/resource_dispatcher_host_delegate.h
diff --git a/content/public/browser/resource_dispatcher_host_delegate.h b/content/public/browser/resource_dispatcher_host_delegate.h
index 181962eee2d3f5ea5f5ce9313e7b87a065cff087..3e66ac3fd1a17aab37e5b8ecd52c61a29e01a74a 100644
--- a/content/public/browser/resource_dispatcher_host_delegate.h
+++ b/content/public/browser/resource_dispatcher_host_delegate.h
@@ -124,6 +124,11 @@ class CONTENT_EXPORT ResourceDispatcherHostDelegate {
   // Notification that a request has completed.
   virtual void RequestComplete(net::URLRequest* url_request);
 
+  // Asks the embedder if Lo-Fi mode should be enabled for the given request. It
+  // is only called for main frame requests with an unspecified Lo-Fi value.

[nasko, 2015/10/15 16:54:43]

nit: "main frame navigation requests", since we don't call this for subresource
requests, right?

[mmenke, 2015/10/15 17:04:28]

Effectively we don't - subresources inherit values from main frame....Main frame
requests may start out with UNSPECIFIED, but once this assigns a value, then
it's passed back to the renderer, and used for all subresource.  That having
been said...There could certainly be some path where subresources are requested
before it's been set for the main frame, so I agree that more weasily language
is probably warranted.

[megjablon, 2015/10/19 22:13:49]

Changed this to just "called for requests." It will be called for anything that
goes through ResourceDispatcherHostImpl::BeginRequest with LOFI_UNSPECIFIED.
Paths where the main frame hasn't set the state yet or there isn't a main frame
request will also call this.

+  virtual bool ShouldEnableLoFiMode(net::URLRequest* url_request,
+                                    content::ResourceContext* resource_context);
+
  protected:
   ResourceDispatcherHostDelegate();
   virtual ~ResourceDispatcherHostDelegate();