Fix several issues with dragging tabs and quickly letting go, including crashes because we get mouseDragged "events" after mouseUp, windows that stay transucent, and windows that vanish entirely but stay in the window list. BUG=22266, 13594, 22538 TEST=dragging tabs between windows should still work Review URL: http://codereview.chromium.org/243080
Fix several issues with dragging tabs and quickly letting go, including crashes because we get mouseDragged "events" after mouseUp, windows that stay transucent, and windows that vanish entirely but stay in the window list.
BUG=22266, 13594, 22538
TEST=dragging tabs between windows should still work
Review URL: http://codereview.chromium.org/243080

git-svn-id: http://src.chromium.org/svn/trunk/src@27861 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 4eaf1e6f87040e9255e44943c8b38fd9a4e597f3
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser