Force-setting default browser through policy should not crash.

The call to set chrome as default browser due to policy needs to happen on the FILE
thread. This change affects the call to set the default browser due to policy at
startup and during runtime.

BUG=101331
TEST=Manual testing performed


Review URL: http://codereview.chromium.org/8409004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@108059 0039d316-1c4b-4281-b951-d872f2087c98
2 files changed