Change transport dib API to not make copies of SharedMemoryHandle.

ui/surface/transport_dib_posix.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 "ui/surface/transport_dib.h"
 
 #include <sys/stat.h>
 #include <unistd.h>
 
 #include "base/logging.h"
@@ skipping 54 matching lines @@
 
 skia::PlatformCanvas* TransportDIB::GetPlatformCanvas(int w, int h) {
   if ((!memory() && !Map()) || !VerifyCanvasSize(w, h))
     return NULL;
   return skia::CreatePlatformCanvas(w, h, true,
                                     reinterpret_cast<uint8_t*>(memory()),
                                     skia::RETURN_NULL_ON_FAILURE);
 }
 
 bool TransportDIB::Map() {
-  if (!is_valid_handle(handle()))
+  if (!is_valid_handle(shared_memory_.handle()))
     return false;
 #if defined(OS_ANDROID)
   if (!shared_memory_.Map(0))
     return false;
   size_ = shared_memory_.mapped_size();
 #else
   if (memory())
     return true;
 
   int size = base::SharedMemory::GetSizeFromSharedMemoryHandle(
       shared_memory_.handle());
   if (size == -1 || !shared_memory_.Map(size))
     return false;
 
   size_ = size;
 #endif
   return true;
 }
 
 void* TransportDIB::memory() const {
   return shared_memory_.memory();
 }
 
 TransportDIB::Id TransportDIB::id() const {
 #if defined(OS_ANDROID)
-  return handle();
+  return shared_memory_.handle();
 #else
   return shared_memory_.id();
 #endif
 }
-
-TransportDIB::Handle TransportDIB::handle() const {
-  return shared_memory_.handle();
-}