Adding reference to experimental browser distribution files.

build/common.gypi

Index: build/common.gypi
===================================================================
--- build/common.gypi	(revision 25950)
+++ build/common.gypi	(working copy)
@@ -69,13 +69,13 @@
     # {'variables': {'library': 'shared_library'}}
     # to compile as shared by default
     'library%': 'static_library',
-    
+
     # The Google Update appid.
     'google_update_appid%': '{8A69D345-D564-463c-AFF1-A69D9E530F96}',
-    
-    # Extra defines to add to built targets
-    'extra_custom_defines%': [],
 
+    # Whether to add the experimental build define.
+    'experimental_build_define%': 0,
+
     # TODO(bradnelson): eliminate this when possible.
     # To allow local gyp files to prevent release.vsprops from being included.
     # Yes(1) means include release.vsprops.
@@ -172,15 +172,15 @@
       'mac_release_optimization%': '3', # Use -O3 unless overridden
       'mac_debug_optimization%': '0'    # Use -O0 unless overridden
     },
-    'defines': [
-      '<@(extra_custom_defines)',
-    ],
     'conditions': [
       ['branding=="Chrome"', {
         'defines': ['GOOGLE_CHROME_BUILD'],
       }, {  # else: branding!="Chrome"
         'defines': ['CHROMIUM_BUILD'],
       }],
+      ['experimental_build_define', {
+        'defines': ['CHROME_EXP_BUILD'],
+      }],
       ['toolkit_views==1', {
         'defines': ['TOOLKIT_VIEWS=1'],
       }],