[BlobAsync] Renderer support for blob file writing.

content/child/blob_storage/blob_message_filter.cc

 // Copyright 2015 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/child/blob_storage/blob_message_filter.h"
 
+#include "base/bind.h"
+#include "base/task_runner.h"
 #include "content/child/blob_storage/blob_transport_controller.h"
 #include "content/child/thread_safe_sender.h"
 #include "content/common/fileapi/webblob_messages.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_sender.h"
 #include "storage/common/blob_storage/blob_item_bytes_request.h"
+#include "storage/common/blob_storage/blob_item_bytes_response.h"
 
 namespace content {
 
-BlobMessageFilter::BlobMessageFilter()
-    : IPC::MessageFilter(), sender_(nullptr) {}
+BlobMessageFilter::BlobMessageFilter(
+    scoped_refptr<base::TaskRunner> io_runner,
+    scoped_refptr<base::TaskRunner> file_runner)
+    : sender_(nullptr),
+      io_runner_(std::move(io_runner)),
+      file_runner_(std::move(file_runner)) {}
 
 BlobMessageFilter::~BlobMessageFilter() {}
 
 void BlobMessageFilter::OnFilterAdded(IPC::Sender* sender) {
   sender_ = sender;
 }
 
+void BlobMessageFilter::OnChannelClosing() {
+  sender_ = nullptr;
+}
+
 bool BlobMessageFilter::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(BlobMessageFilter, message)
     IPC_MESSAGE_HANDLER(BlobStorageMsg_RequestMemoryItem, OnRequestMemoryItem)
     IPC_MESSAGE_HANDLER(BlobStorageMsg_CancelBuildingBlob, OnCancelBuildingBlob)
     IPC_MESSAGE_HANDLER(BlobStorageMsg_DoneBuildingBlob, OnDoneBuildingBlob)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
 bool BlobMessageFilter::GetSupportedMessageClasses(
     std::vector<uint32_t>* supported_message_classes) const {
   supported_message_classes->push_back(BlobMsgStart);
   return true;
 }
 
 void BlobMessageFilter::OnRequestMemoryItem(
     const std::string& uuid,
     const std::vector<storage::BlobItemBytesRequest>& requests,
     std::vector<base::SharedMemoryHandle> memory_handles,
     const std::vector<IPC::PlatformFileForTransit>& file_handles) {
   BlobTransportController::GetInstance()->OnMemoryRequest(
-      uuid, requests, &memory_handles, file_handles, sender_);
+      uuid, requests, &memory_handles, file_handles, io_runner_,
+      file_runner_.get(), base::Bind(&BlobMessageFilter::Send, this));
 }
 
 void BlobMessageFilter::OnCancelBuildingBlob(
     const std::string& uuid,
     storage::IPCBlobCreationCancelCode code) {
   BlobTransportController::GetInstance()->OnCancel(uuid, code);
 }
 
+void BlobMessageFilter::Send(std::unique_ptr<IPC::Message> message) {
+  if (sender_)
+    sender_->Send(message.release());
+}
+
 void BlobMessageFilter::OnDoneBuildingBlob(const std::string& uuid) {
   BlobTransportController::GetInstance()->OnDone(uuid);
 }
 
 }  // namespace content