Refactor ResourceHandler API.

content/browser/loader/navigation_resource_handler.cc

Index: content/browser/loader/navigation_resource_handler.cc
diff --git a/content/browser/loader/navigation_resource_handler.cc b/content/browser/loader/navigation_resource_handler.cc
index dc73b854bea71788845ddf9f8114a42eb1427d92..94458f4b9308c44ddb52976dbc4a7669c0339306 100644
--- a/content/browser/loader/navigation_resource_handler.cc
+++ b/content/browser/loader/navigation_resource_handler.cc
@@ -73,10 +73,10 @@ void NavigationResourceHandler::SetController(ResourceController* controller) {
   ResourceHandler::SetController(controller);
 }
 
-bool NavigationResourceHandler::OnRequestRedirected(
+void NavigationResourceHandler::OnRequestRedirected(
     const net::RedirectInfo& redirect_info,
     ResourceResponse* response,
-    bool* defer) {
+    bool* defer_or_cancel) {
   DCHECK(core_);
 
   // TODO(davidben): Perform a CSP check here, and anything else that would have
@@ -84,12 +84,11 @@ bool NavigationResourceHandler::OnRequestRedirected(
   NetLogObserver::PopulateResponseInfo(request(), response);
   response->head.encoded_data_length = request()->GetTotalReceivedBytes();
   core_->NotifyRequestRedirected(redirect_info, response);
-  *defer = true;
-  return true;
+  *defer_or_cancel = true;
 }
 
-bool NavigationResourceHandler::OnResponseStarted(ResourceResponse* response,
-                                                  bool* defer) {
+void NavigationResourceHandler::OnResponseStarted(ResourceResponse* response,
+                                                  bool* defer_or_cancel) {
   DCHECK(core_);
 
   ResourceRequestInfoImpl* info = GetRequestInfo();
@@ -102,7 +101,7 @@ bool NavigationResourceHandler::OnResponseStarted(ResourceResponse* response,
   // all the way to the UI thread. Downloads, user certificates, etc., should be
   // dispatched at the navigation layer.
   if (info->IsDownload())
-    return true;
+    return;
 
   StreamContext* stream_context =
       GetStreamContextForResourceContext(info->GetContext());
@@ -137,13 +136,11 @@ bool NavigationResourceHandler::OnResponseStarted(ResourceResponse* response,
   // does not work as the InterceptingResourceHandler is above us and hence it
   // does not expect the old handler to defer the request.
   if (!info->is_stream())
-    *defer = true;
-  return true;
+    *defer_or_cancel = true;
 }
 
-bool NavigationResourceHandler::OnWillStart(const GURL& url, bool* defer) {
-  return true;
-}
+void NavigationResourceHandler::OnWillStart(const GURL& url,
+                                            bool* defer_or_cancel) {}
 
 bool NavigationResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                                            int* buf_size,
@@ -152,9 +149,9 @@ bool NavigationResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
   return true;
 }
 
-bool NavigationResourceHandler::OnReadCompleted(int bytes_read, bool* defer) {
-  writer_.OnReadCompleted(bytes_read, defer);
-  return true;
+void NavigationResourceHandler::OnReadCompleted(int bytes_read,
+                                                bool* defer_or_cancel) {
+  writer_.OnReadCompleted(bytes_read, defer_or_cancel);
 }
 
 void NavigationResourceHandler::OnResponseCompleted(