EDK: Move {platform_handle,scoped_platform_handle}.* to //mojo/edk/platform.

mojo/edk/system/message_pipe.h

Index: mojo/edk/system/message_pipe.h
diff --git a/mojo/edk/system/message_pipe.h b/mojo/edk/system/message_pipe.h
index 4e82e0360903307fc6aed0a6bbda415a618d3b00..4f0b1263f8cdbc356a897348236e9a9fa7080c68 100644
--- a/mojo/edk/system/message_pipe.h
+++ b/mojo/edk/system/message_pipe.h
@@ -11,7 +11,7 @@
 #include <memory>
 #include <vector>
 
-#include "mojo/edk/embedder/scoped_platform_handle.h"
+#include "mojo/edk/platform/scoped_platform_handle.h"
 #include "mojo/edk/system/channel_endpoint_client.h"
 #include "mojo/edk/system/dispatcher.h"
 #include "mojo/edk/system/handle_signals_state.h"
@@ -114,7 +114,7 @@ class MessagePipe final : public ChannelEndpointClient {
       Channel* channel,
       void* destination,
       size_t* actual_size,
-      std::vector<embedder::ScopedPlatformHandle>* platform_handles);
+      std::vector<platform::ScopedPlatformHandle>* platform_handles);
 
   // |ChannelEndpointClient| methods:
   bool OnReadMessage(unsigned port, MessageInTransit* message) override;