Switch all windows bots to use Aura.

So we can have the perf bots run with aura for a while. Depending how red
the waterfall we could leave it on for a long time.

This has happened before and it will happen again.
See for example r204698

BUG=259185
TEST=none
TBR=scottmg

Review URL: https://codereview.chromium.org/18434006

git-svn-id: http://src.chromium.org/svn/trunk/src/build@211007 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

common.gypi

@@ -65,8 +65,8 @@
           'branding%': 'Chromium',
 
           'conditions': [
-            # ChromeOS implies ash.
-            ['chromeos==1', {
+            # ChromeOS implies ash and for a limited time Windows. Call now!.
+            ['chromeos==1 or OS=="win"', {
               'use_ash%': 1,
               'use_aura%': 1,
             }],