Revert part of the recent Mac test plugin location change
Revert part of the recent Mac test plugin location change

Fixes WebKit test bustage that only showed up after a clobber; this change needs to be made with a change to pass the new plugin directory argument to TestShell.

TBR=thakis
BUG=None
TEST=Green Mac WebKit bots

Review URL: http://codereview.chromium.org/2868047

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@51731 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