PPAPI/NaCl: Make NaClIPCAdapter transfer handles more generally

gpu/gpu_ipc.gypi

 # 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.
 
 {
   'dependencies': [
     '../ipc/ipc.gyp:ipc',
   ],
   'include_dirs': [
     '..',
     '<(DEPTH)/third_party/khronos',
   ],
   'sources': [
     'ipc/command_buffer_proxy.h',
     'ipc/command_buffer_proxy.cc',
     'ipc/gpu_command_buffer_traits.cc',
     'ipc/gpu_command_buffer_traits.h',
   ],
+  'conditions': [
+    # The NaCl Win64 build only needs the ParamTraits, so we exclude
+    # command_buffer_proxy.*.
+    ['nacl_target==1', {
+      'sources!': [
+        'ipc/command_buffer_proxy.h',
+        'ipc/command_buffer_proxy.cc',
+      ],
+    }],
+  ],
 }