Implement offline mode behind a flag

content/browser/loader/resource_dispatcher_host_impl.cc

Index: content/browser/loader/resource_dispatcher_host_impl.cc
diff --git a/content/browser/loader/resource_dispatcher_host_impl.cc b/content/browser/loader/resource_dispatcher_host_impl.cc
index d69582ea2c130b7c7a3e3e89a5825c7db205de6a..17a9e566fdc798f2c1b3b0c116545f6ef451a1ec 100644
--- a/content/browser/loader/resource_dispatcher_host_impl.cc
+++ b/content/browser/loader/resource_dispatcher_host_impl.cc
@@ -231,8 +231,9 @@ net::Error CallbackAndReturn(
   return net_error;
 }
 
-int BuildLoadFlagsForRequest(const ResourceHostMsg_Request& request_data,
-                             int child_id, bool is_sync_load) {
+int BuildLoadFlagsForRequest(
+    const ResourceHostMsg_Request& request_data, int child_id,

[darin (slow to review), 2013/04/11 20:01:23]

nit: I think the style guide says to put one argument per line when the
arguments start on the line following the function name.

[Randy Smith (Not in Mondays), 2013/04/12 14:06:44]

Wow, right you are.  I wonder if that changed recently--I remembered decls as
being strict and defns as being more freeform (as in the original for this
function).  Done.

+    bool is_sync_load) {
   int load_flags = request_data.load_flags;
 
   // Although EV status is irrelevant to sub-frames and sub-resources, we have
@@ -702,6 +703,10 @@ void ResourceDispatcherHostImpl::DidReceiveRedirect(ResourceLoader* loader,
 
 void ResourceDispatcherHostImpl::DidReceiveResponse(ResourceLoader* loader) {
   ResourceRequestInfoImpl* info = loader->GetRequestInfo();
+  // There should be an entry in the map created when we dispatched the

[darin (slow to review), 2013/04/11 20:01:23]

DCHECK that this is true?  operator[] will create an entry if one doesn't
already exist.

[Randy Smith (Not in Mondays), 2013/04/12 14:06:44]

So my basic response to this is "Sure" and I'll put it in.  However, I'll also
call out the reason I didn't originally put it in, which is that I've seen
guidance on chromium-dev (pkasting@ comes to mind) that if you're going to
dereference a variable, you shouldn't add in the extra DCHECK, and if the
reference creates an entry when it's not there, I believe it'll be NULL, and
that'll result in a crash on the line below.

Done.

+  // request.
+  offline_map_[ProcessRouteIDs(info->GetChildID(), info->GetRouteID())]->

[darin (slow to review), 2013/04/11 20:01:23]

It could also be reasonable for ResourceRequestInfoImpl to have a
GetGlobalRoutingID function.  Hmm, that might be useful elsewhere.

[Randy Smith (Not in Mondays), 2013/04/12 14:06:44]

Done, though it was a bit of a yak shave.  If you have anything more than nits
about this implementation, I'd like to pull it out into a separate CL, just so
that discussion around it doesn't delay this CL.  

One note:  The replacement of "struct GlobalRequestID;" with the inclusion of
the file it was in was the belief that if GlobalRequestID was being used as a
key in maps in rdhi.h the actual structure needed to be known by rdhi.h,
semi-confirmed by successfully compiling with the "struct GlobalRequestID;"
removed, followed by putting the include in for IWYU.  If you object to any of
that I can reverse it, but it made sense at the time :-}.

+      RequestCompleted(loader->request()->response_info());
 
   int render_process_id, render_view_id;
   if (!info->GetAssociatedRenderView(&render_process_id, &render_view_id))
@@ -936,6 +941,12 @@ void ResourceDispatcherHostImpl::BeginRequest(
   int load_flags =
       BuildLoadFlagsForRequest(request_data, child_id, is_sync_load);
 
+  ProcessRouteIDs id(child_id, route_id);
+  if (!offline_map_[id])
+    offline_map_[id] = new OfflinePolicy();
+  load_flags |= offline_map_[id]->GetAdditionalLoadFlags(
+      load_flags, request_data.resource_type);
+
   // Construct the request.
   scoped_ptr<net::URLRequest> new_request;
   net::URLRequest* request;
@@ -1371,6 +1382,10 @@ void ResourceDispatcherHostImpl::CancelRequestsForRoute(int child_id,
       CancelBlockedRequestsForRoute(child_id, *iter);
     }
   }
+
+  // Cleanup the offline state for the route.
+  delete offline_map_[ProcessRouteIDs(child_id, route_id)];
+  offline_map_.erase(ProcessRouteIDs(child_id, route_id));
 }
 
 // Cancels the request and removes it from the list.