Move refresh_tokens_ to MutableProfileOAuth2TokenService.

This CL moves refresh_tokens_ from ProfileOAuth2TokenService to
MutableProfileOAuth2TokenService. It also removes some unused private
methods from ProfileOAuth2TokenService.

R=rogerta
TBR=sky, rohitrao
BUG=320625

Review URL: https://codereview.chromium.org/114513003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244591 0039d316-1c4b-4281-b951-d872f2087c98
Update QuickOffice to version 34.97.1922.1

BUG=332884
TEST=manual
NOTRY=true

Review URL: https://codereview.chromium.org/134553004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244592 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 244592