gtk: make right-clicking on task manager body show menu again
gtk: make right-clicking on task manager body show menu again

My change to make it show on mouse-down rather than up regressed this.

While I'm here, make it so we show the first column full title as a tooltip.

BUG=73081

Review URL: http://codereview.chromium.org/6580003

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@75802 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser