include.gypi variables to specify API keys or use internal header for keys.

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 873 matching lines @@
     # has no full v8 debug, has size optimization and linker gc section, so that
     # we can build a debug version with acceptable size and performance.
     'android_full_debug%': 0,
 
     'sas_dll_exists': '<!(python <(DEPTH)/build/dir_exists.py <(sas_dll_path))',
     'wix_exists': '<!(python <(DEPTH)/build/dir_exists.py <(wix_path))',
 
     'windows_sdk_default_path': '<(DEPTH)/third_party/platformsdk_win8/files',
     'directx_sdk_default_path': '<(DEPTH)/third_party/directxsdk/files',
 
+    # Set these to bake API keys and OAuth client IDs/secrets into
+    # your build.  If they are not baked in, you can instead set
+    # environment variables to provide the keys at runtime (see
+    # src/google_apis/google_api_keys.h for details).  Features that
+    # require server-side APIs may fail to work if no keys are
+    # provided.
+    #
+    # Note that if you are building an official build or if you set
+    # use_official_google_api_keys to 1, these values will be ignored
+    # and the official keys will be used instead.
+    'google_api_key%': '',
+    'google_default_client_id%': '',
+    'google_default_client_secret%': '',
+
+    # Set this to 1 to use the Google-internal file containing
+    # official API keys for Google Chrome even in a developer build.
+    'use_official_google_api_keys%': 0,
+
     'conditions': [
       ['OS=="win" and "<!(python <(DEPTH)/build/dir_exists.py <(windows_sdk_default_path))"=="True"', {
         'windows_sdk_path%': '<(windows_sdk_default_path)',
       }, {
         'windows_sdk_path%': 'C:/Program Files (x86)/Windows Kits/8.0',
       }],
       ['OS=="win" and "<!(python <(DEPTH)/build/dir_exists.py <(directx_sdk_default_path))"=="True"', {
         'directx_sdk_path%': '<(directx_sdk_default_path)',
       }, {
         'directx_sdk_path%': '$(DXSDK_DIR)',
@@ skipping 2527 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',
   },
 }