Reland: Misc cleanup in Drive/Files.app C++ code.

BUG=none

Prev Commit: https://src.chromium.org/viewvc/chrome?view=rev&revision=240957
Reverted: https://src.chromium.org/viewvc/chrome?view=rev&revision=240967

Review URL: https://codereview.chromium.org/116983003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241526 0039d316-1c4b-4281-b951-d872f2087c98
Add base:: prefix to string16 in net/.

R=mattm@chromium.org
BUG=329295
TEST=compile

Review URL: https://codereview.chromium.org/117233007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241527 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 241527