BUG=9094
BUG=9094

GetRequestContextForMedia() in ProfileImpl and OffTheRecordProfileImpl
now respect --disk-cache-dir. Since the snippet for getting the path
from --disk-cache-dir is very short, it's not necessary to keep it in
a separate method so I duplicated the snippet and used it in both
classes.

Review URL: http://codereview.chromium.org/42517

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@12298 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