[Android WebView] Implement the capture picture API.

ipc/ipc_channel_proxy.cc

 // Copyright (c) 2012 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 "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/debug/trace_event.h"
 #include "base/location.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 50 matching lines @@
   ipc_task_runner_ = NULL;
 }
 
 void ChannelProxy::Context::CreateChannel(const IPC::ChannelHandle& handle,
                                           const Channel::Mode& mode) {
   DCHECK(channel_.get() == NULL);
   channel_id_ = handle.name;
   channel_.reset(new Channel(handle, mode, this));
 }
 
+void ChannelProxy::Context::SendFailedSyncMessageReply(const Message& message) {
+  if (!message.is_sync())
+    return;
+
+  Message* reply = SyncMessage::GenerateReply(&message);
+  reply->set_reply_error();
+  ipc_task_runner()->PostTask(
+    FROM_HERE,
+    base::Bind(&ChannelProxy::Context::OnSendMessage,
+               this, base::Passed(scoped_ptr<Message>(reply))));
+}
+
 bool ChannelProxy::Context::TryFilters(const Message& message) {
 #ifdef IPC_MESSAGE_LOG_ENABLED
   Logging* logger = Logging::GetInstance();
   if (logger->Enabled())
     logger->OnPreDispatchMessage(message);
 #endif
 
   for (size_t i = 0; i < filters_.size(); ++i) {
     if (filters_[i]->OnMessageReceived(message)) {
 #ifdef IPC_MESSAGE_LOG_ENABLED
@@ skipping 155 matching lines @@
   std::string name;
   logger->GetMessageText(message.type(), &name, &message, NULL);
   TRACE_EVENT1("task", "ChannelProxy::Context::OnDispatchMessage",
                "name", name);
 #else
   TRACE_EVENT2("task", "ChannelProxy::Context::OnDispatchMessage",
                "class", IPC_MESSAGE_ID_CLASS(message.type()),
                "line", IPC_MESSAGE_ID_LINE(message.type()));
 #endif
 
-  if (!listener_)
+  if (!listener_) {
+    SendFailedSyncMessageReply(message);
     return;
+  }
 
   OnDispatchConnected();
 
 #ifdef IPC_MESSAGE_LOG_ENABLED
   if (message.type() == IPC_LOGGING_ID) {
     logger->OnReceivedLoggingMessage(message);
+    SendFailedSyncMessageReply(message);
     return;
   }
 
   if (logger->Enabled())
     logger->OnPreDispatchMessage(message);
 #endif
 
-  listener_->OnMessageReceived(message);
+  if (!listener_->OnMessageReceived(message))
+    SendFailedSyncMessageReply(message);
 
 #ifdef IPC_MESSAGE_LOG_ENABLED
   if (logger->Enabled())
     logger->OnPostDispatchMessage(message, channel_id_);
 #endif
 }
 
 // Called on the listener's thread
 void ChannelProxy::Context::OnDispatchConnected() {
   if (channel_connected_called_)
@@ skipping 148 matching lines @@
   Channel* channel = context_.get()->channel_.get();
   // Channel must have been created first.
   DCHECK(channel) << context_.get()->channel_id_;
   return channel->GetClientEuid(client_euid);
 }
 #endif
 
 //-----------------------------------------------------------------------------
 
 }  // namespace IPC