Indicate which authentication flow was used in UserContext

This CL adds a field to UserContext that indicates which authentication
flow was used (online without SAML, online with SAML, offline). This
distinction will be used to implement a policy that forces SAML users to
log in via the online authentication flow periodically.

BUG=332081
TEST=Manual (automated tests coming in follow-up CL that adds the policy)

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=246674

Review URL: https://codereview.chromium.org/145073003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246896 0039d316-1c4b-4281-b951-d872f2087c98
Migrate remoting/ to base::RunLoop::RunUntilIdle();

base::MessageLoop::RunUntilIdle() API is deprecated and the preferred
way is using RunLoop now.

BUG=333558
TEST=remoting_unittests
R=sergeyu@chromium.org,wez@chromium.org

Review URL: https://codereview.chromium.org/144753006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246897 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 246896
SVN changes up to revision 246897
[WebSocket] Compress an empty string to one byte.

Currently permessage-deflate deflater compresses an empty string to a
two-byte string "\x02\x00". It should be "\x00" to save space.

BUG=337781
R=tyoshino

Review URL: https://codereview.chromium.org/146643002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246898 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 246898