Http cache: Delete the response headers when the network transaction is re-created, and make sure that truncated_ is also creared.
Http cache: Delete the response headers when the network transaction
is re-created, and make sure that truncated_ is also creared.

This is a tentative fix for some crashes from the reliability bot.

BUG=28850
TEST=none
TBR=eroman

Review URL: http://codereview.chromium.org/444020

git-svn-id: http://src.chromium.org/svn/trunk/src@33251 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 237cda3814b2f2158d9addb165f8d968e9e50cb9
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser