[Mac] Delete more bookmark bar folder code. This removes things that were missed last time.

One of the issues is that a nested event loop in |-mouseDown:| was causing the
thread to block after the menu closes, because the opening of the menu pumps the
mouseUp event.

BUG=91850
TEST=Open a bookmark from the folder and the spinner spins.

Review URL: http://codereview.chromium.org/7528007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@95901 0039d316-1c4b-4281-b951-d872f2087c98
11 files changed