GitLab

There is an issue which overwrites the download_data_ if the pending
data is not yet consumed. This CL fixes it.

BUG=223603
TEST=Ran unit_tests and tested manually.

Review URL: https://codereview.chromium.org/13065007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@190561 0039d316-1c4b-4281-b951-d872f2087c98