Fixing memleak found by purify.
Fixing memleak found by purify.

This should fix leaks at:
extensions_service.cc:495 and 498
... and since the providers are getting cleaned up, it should take care of:
extensions_service.cc:211
... as well.

TBR=erikkay
TEST=Covered by automated tests.
BUG=None

Review URL: http://codereview.chromium.org/126037

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@18251 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