[Android] Make build/gyp_chromium runnable on Android.

I messed up the parentheses in https://codereview.chromium.org/1952033002/,
which made running build/gyp_chromium on Android impossible.

BUG=

Review-Url: https://codereview.chromium.org/1947423003
Cr-Commit-Position: refs/heads/master@{#391938}

build/gyp_chromium.py

@@ -326,8 +326,8 @@ def main():
   running_as_hook = '--running-as-hook'
   if (running_as_hook in args and
       os.environ.get('GYP_CHROMIUM_NO_ACTION', None) != '0' and
-      ((sys.platform.startswith('linux') and not gyp_vars_dict)) or
-       (gyp_vars_dict.get('OS') == 'android')):
+      ((sys.platform.startswith('linux') and not gyp_vars_dict) or
+       (gyp_vars_dict.get('OS') == 'android'))):
     print 'GYP is now disabled in this configuration by default in runhooks.\n'
     print 'If you really want to run this, either run '
     print '`python build/gyp_chromium.py` explicitly by hand'