Make ResourceHandler::OnWillRead able to complete asynchronously.

content/browser/loader/navigation_resource_handler.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/loader/navigation_resource_handler.h"
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/logging.h"
@@ skipping 136 matching lines @@
   }
 }
 
 void NavigationResourceHandler::OnWillStart(
     const GURL& url,
     std::unique_ptr<ResourceController> controller) {
   DCHECK(!has_controller());
   controller->Resume();
 }
 
-bool NavigationResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
-                                           int* buf_size) {
+void NavigationResourceHandler::OnWillRead(
+    scoped_refptr<net::IOBuffer>* buf,
+    int* buf_size,
+    std::unique_ptr<ResourceController> controller) {
   DCHECK(!has_controller());
   writer_.OnWillRead(buf, buf_size, -1);
-  return true;
+  controller->Resume();
 }
 
 void NavigationResourceHandler::OnReadCompleted(
     int bytes_read,
     std::unique_ptr<ResourceController> controller) {
   DCHECK(!has_controller());
   writer_.OnReadCompleted(bytes_read,
                           base::Bind(&ResourceController::Resume,
                                      base::Passed(std::move(controller))));
 }
@@ skipping 21 matching lines @@
   NOTREACHED();
 }
 
 void NavigationResourceHandler::DetachFromCore() {
   DCHECK(core_);
   core_->set_resource_handler(nullptr);
   core_ = nullptr;
 }
 
 }  // namespace content