Ensure that SAML IdPs use https on Chrome OS

This CL sets a CSP for the GAIA auth extension that ensures the entire
login flow, including redirects to SAML IdPs, uses https.

The FakeGaia and FakeSamlIdp classes used in SAML tests use the embedded
test server, which speaks http only. The CL therefore adds a test server
written in Python that speaks https and acts as a wrapper by forwarding
calls to the embedded test server over http.

TBR=asargent@chromium.org (for gaia_auth_extension_loader.cc)

BUG=337437
TEST=Full browser test coverage

Review URL: https://codereview.chromium.org/150483002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250114 0039d316-1c4b-4281-b951-d872f2087c98
[Ozone] Update DriSkPixelRef implementation to match skia changes

TBR=rjkroege@chromium.org
NOTRY=true

TEST=Compiled content_shell on Ozone

Review URL: https://codereview.chromium.org/148353005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250115 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 250115