athena: Move the USE_ATHENA define into //chrome.

chrome/chrome_browser.gypi

 # Copyright 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': {
     # All .cc, .h, .m, and .mm files under browser except for:
     # * tests and mocks.
     # * code below browser/chromeos
     # * code below browser/extensions
@@ skipping 2936 matching lines @@
 
             # These files are generated by GRIT.
             '<(grit_out_dir)/grit/component_extension_resources_map.cc',
             '<(grit_out_dir)/grit/theme_resources_map.cc',
             '<(SHARED_INTERMEDIATE_DIR)/ui/resources/grit/ui_resources_map.cc',
 
             # This file is generated by
             # chrome/browser/metrics/variations/generate_resources_map.py
             '<(SHARED_INTERMEDIATE_DIR)/chrome/browser/metrics/variations/generated_resources_map.cc',
           ],
+          'conditions': [
+            ['use_athena==1', {
+              'defines': ['USE_ATHENA=1'],
+            }],
+          ],
           'defines': [
             '<@(nacl_defines)',
           ],
           'direct_dependent_settings': {
             'defines': [
               '<@(nacl_defines)',
             ],
           },
         }, {  # OS == "ios"
           'dependencies': [
@@ skipping 601 matching lines @@
           'variables': {
             'proto_in_dir': 'browser/sync_file_system/drive_backend',
             'proto_out_dir': 'chrome/browser/sync_file_system/drive_backend',
           },
           'includes': [ '../build/protoc.gypi' ]
         },
       ],
     },],
   ],
 }