Drop ENABLE_NEW_GAMEPAD_API build flag as it is no longer needed

build/common.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.
 
 # IMPORTANT:
 # Please don't directly include this file if you are building via gyp_chromium,
 # since gyp_chromium is automatically forcing its inclusion.
 {
   # Variables expected to be overriden on the GYP command line (-D) or by
   # ~/.gyp/include.gypi.
@@ skipping 2270 matching lines @@
       'enable_wexit_time_destructors%': '<(enable_wexit_time_destructors)',
 
       # Only used by Windows build for now.  Can be used to build into a
       # differet output directory, e.g., a build_dir_prefix of VS2010_ would
       # output files in src/build/VS2010_{Debug,Release}.
       'build_dir_prefix%': '',
 
       # Targets are by default not nacl untrusted code.
       'nacl_untrusted_build%': 0,
 
-      # Enable a new Gamepad interface.
-      # TODO(cdumez): This is temporary and should go away once the chromium
-      # and blink interfaces are in sync, http://crbug.com/344556.
-      'enable_new_gamepad_api%': 1,
-
       'pnacl_compile_flags': [
         # pnacl uses the clang compiler so we need to suppress all the
         # same warnings as we do for clang.
         # TODO(sbc): Remove these if/when they are removed from the clang
         # build.
         '-Wno-unused-function',
         '-Wno-char-subscripts',
         '-Wno-c++11-extensions',
         '-Wno-unnamed-type-template-args',
       ],
@@ skipping 149 matching lines @@
       }],
       ['configuration_policy==1', {
         'defines': ['ENABLE_CONFIGURATION_POLICY'],
       }],
       ['notifications==1', {
         'defines': ['ENABLE_NOTIFICATIONS'],
       }],
       ['enable_hidpi==1', {
         'defines': ['ENABLE_HIDPI=1'],
       }],
-      ['enable_new_gamepad_api==1', {
-        'defines': ['ENABLE_NEW_GAMEPAD_API=1'],
-      }],
       ['native_discardable_memory==1', {
         'defines': ['DISCARDABLE_MEMORY_ALWAYS_SUPPORTED_NATIVELY'],
       }],
       ['native_memory_pressure_signals==1', {
         'defines': ['SYSTEM_NATIVELY_SIGNALS_MEMORY_PRESSURE'],
       }],
       ['use_udev==1', {
         'defines': ['USE_UDEV'],
       }],
       ['fastbuild!=0', {
@@ skipping 2901 matching lines @@
     # settings in target dicts.  SYMROOT is a special case, because many other
     # Xcode variables depend on it, including variables such as
     # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
     # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
     # files to appear (when present) in the UI as actual files and not red
     # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
     # and therefore SYMROOT, needs to be set at the project level.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }