Eliminate the 'build_ppapi_ipc_proxy_untrusted' build flag for untrusted PPAPI proxy builds.

ppapi/ppapi_proxy_untrusted.gyp

-# 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.
-
-{
-  'variables': {
-    'chromium_code': 1,
-  },
-  'includes': [
-    '../native_client/build/untrusted.gypi',
-    'ppapi_proxy.gypi',
-  ],
-  'conditions': [
-    ['disable_nacl==0 and disable_nacl_untrusted==0', {
-      'targets': [
-        {
-          'target_name': 'ppapi_proxy_untrusted',
-          'type': 'none',
-          'variables': {
-            'ppapi_proxy_target': 1,
-            'nacl_untrusted_build': 1,
-            'nlib_target': 'libppapi_proxy_untrusted.a',
-            'build_glibc': 0,
-            'build_newlib': 1,
-          },
-          'defines': [
-            'NACL_PPAPI_IPC_PROXY',
-          ],
-          'include_dirs': [
-            '..',
-            '../third_party/khronos',
-          ],
-          'dependencies': [
-            '../native_client/tools.gyp:prep_toolchain',
-            '../base/base_untrusted.gyp:base_untrusted',
-            '../gpu/command_buffer/command_buffer_untrusted.gyp:gles2_utils_untrusted',
-            '../gpu/gpu_untrusted.gyp:command_buffer_client_untrusted',
-            '../gpu/gpu_untrusted.gyp:command_buffer_common_untrusted',
-            '../gpu/gpu_untrusted.gyp:gles2_implementation_untrusted',
-            '../gpu/gpu_untrusted.gyp:gles2_cmd_helper_untrusted',
-            '../gpu/gpu_untrusted.gyp:gpu_ipc_untrusted',
-            '../ipc/ipc_untrusted.gyp:ipc_untrusted',
-            '../ppapi/ppapi_shared_untrusted.gyp:ppapi_shared_untrusted',
-          ],
-        },
-      ],
-    }],
-  ],
-}