Adds sync brokering to Windows EDK

mojo/edk/system/broker_host.h

 // Copyright 2016 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.
 
 #ifndef MOJO_EDK_SYSTEM_BROKER_HOST_H_
 #define MOJO_EDK_SYSTEM_BROKER_HOST_H_
 
 #include "base/macros.h"
 #include "base/message_loop/message_loop.h"
+#include "base/process/process_handle.h"
+#include "mojo/edk/embedder/platform_handle_vector.h"
 #include "mojo/edk/embedder/scoped_platform_handle.h"
 #include "mojo/edk/system/channel.h"
 
 namespace mojo {
 namespace edk {
 
 // The BrokerHost is a channel to the child process, which services synchronous
 // IPCs.
 class BrokerHost : public Channel::Delegate,
                    public base::MessageLoop::DestructionObserver {
  public:
-  explicit BrokerHost(ScopedPlatformHandle platform_handle);
+  BrokerHost(base::ProcessHandle client_process, ScopedPlatformHandle handle);
 
   // Send |handle| to the child, to be used to establish a NodeChannel to us.
   void SendChannel(ScopedPlatformHandle handle);
 
  private:
   ~BrokerHost() override;
 
+  void PrepareHandlesForClient(PlatformHandleVector* handles);
+
   // Channel::Delegate:
   void OnChannelMessage(const void* payload,
                         size_t payload_size,
                         ScopedPlatformHandleVectorPtr handles) override;
   void OnChannelError() override;
 
   // base::MessageLoop::DestructionObserver:
   void WillDestroyCurrentMessageLoop() override;
 
   void OnBufferRequest(size_t num_bytes);
 
+#if defined(OS_WIN)
+  base::ProcessHandle client_process_;
+#endif
+
   scoped_refptr<Channel> channel_;
 
   DISALLOW_COPY_AND_ASSIGN(BrokerHost);
 };
 
 }  // namespace edk
 }  // namespace mojo
 
 #endif  // MOJO_EDK_SYSTEM_BROKER_HOST_H_