[Mac] Enable click-drag-release behavior in the Wrench menu's custom items.

XIB changes:
* Replace the edit item's segmented control with 3 buttons
* Make the root view of both items a MenuTrackedRootView
* Use the custom MenuTrackedButton for all the buttons

BUG=49356
TEST=Click open the Wrench menu, hold, and drag over the buttons and they perform their function.

Review URL: http://codereview.chromium.org/3072014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@54804 0039d316-1c4b-4281-b951-d872f2087c98
12 files changed