Revert of Use Mojo pipes to signal sync IPC events

ppapi/ppapi_internal.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,  # Use higher warning level.
   },
   'target_defaults': {
     'conditions': [
@@ skipping 93 matching lines @@
             'ppapi_proxy_target': 1,
           },
           'dependencies': [
             '../base/base.gyp:base',
             '../base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
             '../gin/gin.gyp:gin',
             '../gpu/gpu.gyp:gles2_implementation',
             '../gpu/gpu.gyp:command_buffer_traits',
             '../media/media.gyp:shared_memory_support',
             '../ipc/ipc.gyp:ipc',
-            '../mojo/mojo_edk.gyp:mojo_system_impl',
             '../skia/skia.gyp:skia',
             '../third_party/icu/icu.gyp:icuuc',
             '../third_party/icu/icu.gyp:icui18n',
             '../ui/surface/surface.gyp:surface',
             'ppapi.gyp:ppapi_c',
             'ppapi_shared',
             'ppapi_ipc',
           ],
           'all_dependent_settings': {
             'include_dirs': [
@@ skipping 27 matching lines @@
             'ppapi_ipc_target': 1,
             'ppapi_proxy_target': 1,
           },
           'dependencies': [
             '../base/base.gyp:base',
             '../base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
             '../gin/gin.gyp:gin',
             '../gpu/gpu.gyp:gles2_implementation',
             '../gpu/gpu.gyp:command_buffer_traits',
             '../media/media.gyp:shared_memory_support',
-            '../mojo/mojo_edk.gyp:mojo_system_impl',
             '../ipc/ipc.gyp:ipc',
             '../skia/skia.gyp:skia',
             '../third_party/icu/icu.gyp:icuuc',
             '../third_party/icu/icu.gyp:icui18n',
             '../ui/surface/surface.gyp:surface',
             'ppapi.gyp:ppapi_c',
             'ppapi_shared',
           ],
           'all_dependent_settings': {
             'include_dirs': [
@@ skipping 86 matching lines @@
           },
           'configurations': {
             'Common_Base': {
               'msvs_target_platform': 'x64',
             },
           },
       }],
     }],
   ],
 }