Revert of Remove webkit's ResourceLoaderBridge interface.

content/child/web_url_loader_impl.cc

Index: content/child/web_url_loader_impl.cc
diff --git a/content/child/web_url_loader_impl.cc b/content/child/web_url_loader_impl.cc
index 1da8082e057769e6e964836ecb01dae4bdcc9499..7724a50e6e0c7b6bb89f0d2e5331d552d2ebe979 100644
--- a/content/child/web_url_loader_impl.cc
+++ b/content/child/web_url_loader_impl.cc
@@ -1,6 +1,8 @@
 // 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.
+
+// An implementation of WebURLLoader in terms of ResourceLoaderBridge.
 
 #include "content/child/web_url_loader_impl.h"
 
@@ -14,9 +16,7 @@
 #include "content/child/ftp_directory_listing_response_delegate.h"
 #include "content/child/request_extra_data.h"
 #include "content/child/request_info.h"
-#include "content/child/resource_dispatcher.h"
 #include "content/child/sync_load_response.h"
-#include "content/common/resource_messages.h"
 #include "content/common/resource_request_body.h"
 #include "content/public/child/request_peer.h"
 #include "net/base/data_url.h"
@@ -37,6 +37,7 @@
 #include "third_party/WebKit/public/platform/WebURLResponse.h"
 #include "third_party/WebKit/public/web/WebSecurityPolicy.h"
 #include "webkit/child/multipart_response_delegate.h"
+#include "webkit/child/resource_loader_bridge.h"
 #include "webkit/child/weburlresponse_extradata_impl.h"
 
 using base::Time;
@@ -57,6 +58,7 @@
 using blink::WebURLResponse;
 using webkit_glue::MultipartResponseDelegate;
 using webkit_glue::ResourceDevToolsInfo;
+using webkit_glue::ResourceLoaderBridge;
 using webkit_glue::ResourceResponseInfo;
 using webkit_glue::WebURLResponseExtraDataImpl;
 
@@ -257,7 +259,7 @@
 
  private:
   friend class base::RefCounted<Context>;
-  virtual ~Context();
+  virtual ~Context() {}
 
   // We can optimize the handling of data URLs in most cases.
   bool CanHandleDataURL(const GURL& url) const;
@@ -267,21 +269,23 @@
   WebURLRequest request_;
   WebURLLoaderClient* client_;
   WebReferrerPolicy referrer_policy_;
+  scoped_ptr<ResourceLoaderBridge> bridge_;
   scoped_ptr<FtpDirectoryListingResponseDelegate> ftp_listing_delegate_;
   scoped_ptr<MultipartResponseDelegate> multipart_delegate_;
-  int request_id_;
+  scoped_ptr<ResourceLoaderBridge> completed_bridge_;
 };
 
 WebURLLoaderImpl::Context::Context(WebURLLoaderImpl* loader)
     : loader_(loader),
       client_(NULL),
-      referrer_policy_(blink::WebReferrerPolicyDefault),
-      request_id_(-1) {
+      referrer_policy_(blink::WebReferrerPolicyDefault) {
 }
 
 void WebURLLoaderImpl::Context::Cancel() {
-  if (ChildThread::current())  // NULL in unittest.
-    ChildThread::current()->resource_dispatcher()->Cancel(request_id_);
+  // The bridge will still send OnCompletedRequest, which will Release() us, so
+  // we don't do that here.
+  if (bridge_)
+    bridge_->Cancel();
 
   // Ensure that we do not notify the multipart delegate anymore as it has
   // its own pointer to the client.
@@ -294,21 +298,21 @@
 }
 
 void WebURLLoaderImpl::Context::SetDefersLoading(bool value) {
-  ChildThread::current()->resource_dispatcher()->SetDefersLoading(request_id_,
-                                                                  value);
+  if (bridge_)
+    bridge_->SetDefersLoading(value);
 }
 
 void WebURLLoaderImpl::Context::DidChangePriority(
-    WebURLRequest::Priority new_priority,
-    int intra_priority_value) {
-  ChildThread::current()->resource_dispatcher()->DidChangePriority(
-      request_id_,
-      ConvertWebKitPriorityToNetPriority(new_priority),
-      intra_priority_value);
+    WebURLRequest::Priority new_priority, int intra_priority_value) {
+  if (bridge_)
+    bridge_->DidChangePriority(
+        ConvertWebKitPriorityToNetPriority(new_priority), intra_priority_value);
 }
 
 void WebURLLoaderImpl::Context::Start(const WebURLRequest& request,
                                       SyncLoadResponse* sync_load_response) {
+  DCHECK(!bridge_.get());
+
   request_ = request;  // Save the request.
 
   GURL url = request.url();
@@ -396,10 +400,7 @@
   request_info.extra_data = request.extraData();
   referrer_policy_ = request.referrerPolicy();
   request_info.referrer_policy = request.referrerPolicy();
-  ResourceDispatcher* dispatcher =
-      ChildThread::current()->resource_dispatcher();
-
-  scoped_refptr<ResourceRequestBody> request_body = new ResourceRequestBody;
+  bridge_.reset(ChildThread::current()->CreateBridge(request_info));
 
   if (!request.httpBody().isNull()) {
     // GET and HEAD requests shouldn't have http bodies.
@@ -407,6 +408,7 @@
     const WebHTTPBody& httpBody = request.httpBody();
     size_t i = 0;
     WebHTTPBody::Element element;
+    scoped_refptr<ResourceRequestBody> request_body = new ResourceRequestBody;
     while (httpBody.elementAt(i++, element)) {
       switch (element.type) {
         case WebHTTPBody::Element::TypeData:
@@ -448,16 +450,19 @@
       }
     }
     request_body->set_identifier(request.httpBody().identifier());
-
+    bridge_->SetRequestBody(request_body.get());
   }
 
   if (sync_load_response) {
-    dispatcher->StartSync(request_info, request_body.get(), sync_load_response);
+    bridge_->SyncLoad(sync_load_response);
     return;
   }
 
-  AddRef();  // Balanced in OnCompletedRequest.
-  request_id_ = dispatcher->StartAsync(request_info, request_body.get(), this);
+  if (bridge_->Start(this)) {
+    AddRef();  // Balanced in OnCompletedRequest
+  } else {
+    bridge_.reset();
+  }
 }
 
 void WebURLLoaderImpl::Context::OnUploadProgress(uint64 position, uint64 size) {
@@ -594,8 +599,8 @@
   }
 }
 
-void WebURLLoaderImpl::Context::OnReceivedCachedMetadata(const char* data,
-                                                         int len) {
+void WebURLLoaderImpl::Context::OnReceivedCachedMetadata(
+    const char* data, int len) {
   if (client_)
     client_->didReceiveCachedMetadata(loader_, data, len);
 }
@@ -615,6 +620,11 @@
     multipart_delegate_.reset(NULL);
   }
 
+  // Prevent any further IPC to the browser now that we're complete, but
+  // don't delete it to keep any downloaded temp files alive.
+  DCHECK(!completed_bridge_.get());
+  completed_bridge_.swap(bridge_);
+
   if (client_) {
     if (error_code != net::OK) {
       client_->didFail(loader_, CreateError(request_.url(),
@@ -633,13 +643,6 @@
   Release();
 }
 
-WebURLLoaderImpl::Context::~Context() {
-  if (request_id_ >= 0) {
-    ChildThread::current()->resource_dispatcher()->RemovePendingRequest(
-        request_id_);
-  }
-}
-
 bool WebURLLoaderImpl::Context::CanHandleDataURL(const GURL& url) const {
   DCHECK(url.SchemeIs("data"));
 
@@ -648,7 +651,8 @@
   // download.
   //
   // NOTE: We special case MIME types we can render both for performance
-  // reasons as well as to support unit tests.
+  // reasons as well as to support unit tests, which do not have an underlying
+  // ResourceLoaderBridge implementation.
 
 #if defined(OS_ANDROID)
   // For compatibility reasons on Android we need to expose top-level data://