Rebuild Views Textfield context menu runner on each showing.
Without rebuilding, stale command states are used.
That may leave menu items incorrectly enabled/disabled.
Fixes a regression from http://crrev.com/244436
BUG=334604
TEST=Bug doesn't repro; omnibox and textfield context menu items are enabled or disabled as expected on each menu invocation.
R=sky@chromium.org
Review URL: https://codereview.chromium.org/
137893017
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245461 0039d316-1c4b-4281-b951-d872f2087c98