Rearrange gyp files for Message Center

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index 92b34c8af7c20faefba751b29c4426382dfee938..749a0011893f934f0cabc0286e61a423822590bb 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -135,11 +135,14 @@
             'enable_touch_ui%': 1,
           }],
 
-          # Enable App Launcher only on ChromeOS and Windows for now.
+          # Enable App Launcher & Message Center only on ChromeOS and Windows
+          # for now.
           ['use_ash==1 or OS=="win"', {
             'enable_app_list%': 1,
+            'enable_message_center%': 1,
           }, {
             'enable_app_list%': 0,
+            'enable_message_center%': 0,
           }],
 
           ['use_aura==1 or (OS!="win" and OS!="mac" and OS!="ios" and OS!="android")', {
@@ -165,6 +168,7 @@
       'enable_touch_ui%': '<(enable_touch_ui)',
       'android_build_type%': '<(android_build_type)',
       'enable_app_list%': '<(enable_app_list)',
+      'enable_message_center%': '<(enable_message_center)',
       'use_default_render_theme%': '<(use_default_render_theme)',
       'buildtype%': '<(buildtype)',
 
@@ -716,6 +720,7 @@
     'use_system_libjpeg%': '<(use_system_libjpeg)',
     'android_build_type%': '<(android_build_type)',
     'enable_app_list%': '<(enable_app_list)',
+    'enable_message_center%': '<(enable_message_center)',
     'use_default_render_theme%': '<(use_default_render_theme)',
     'enable_settings_app%': '<(enable_settings_app)',
     'use_official_google_api_keys%': '<(use_official_google_api_keys)',
@@ -1917,6 +1922,9 @@
       ['enable_app_list==1', {
         'defines': ['ENABLE_APP_LIST=1'],
       }],
+      ['enable_message_center==1', {
+        'defines': ['ENABLE_MESSAGE_CENTER=1'],
+      }],
       ['enable_settings_app==1', {
         'defines': ['ENABLE_SETTINGS_APP=1'],
       }],