Switch to python2.6 as the default for pyauto on linux

BUG=81621

R=cmp@chromium.org
TEST=

Review URL: http://codereview.chromium.org/6992077

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@86732 0039d316-1c4b-4281-b951-d872f2087c98

build/common.gypi

@@ -98,7 +98,7 @@
       'file_manager_extension%': 0,
 
       # Python version.
-      'python_ver%': '2.5',
+      'python_ver%': '2.6',
 
       # Set ARM-v7 compilation flags
       'armv7%': 0,