Rewrite Google Code http URLs with https on git svn dcommit.

This fix is created to avoid having to rebuild all the WebRTC
Git mirrors since they're configured to sync with the http URL
instead of https (resulting in git-svn-id Git footers with the
http URL in the commit messages). Without rewriting this, it is
not possible to commit to SVN since Google code disallows committing
to a http URL.

BUG=412012
TEST=Created a CL using a Git repo like this (both before and after landing https://webrtc-codereview.appspot.com/32569004):
git clone https://chromium.googlesource.com/external/webrtc.git
cd webrtc
git auto-svn
git checkout master
git checkout -b test
(edit whitespace change)
git commit -am "Whitespace edit
git cl upload --bypass-hooks"
git cl dcommit

R=agable@chromium.org, machenbach@chromium.org, mmoss@chromium.org

Review URL: https://codereview.chromium.org/760903004

git-svn-id: http://src.chromium.org/chrome/trunk/tools/depot_tools@293171 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Add scottmg to depot_tools/win_toolchain OWNERS

R=dpranke@chromium.org

Review URL: https://codereview.chromium.org/771233002

git-svn-id: http://src.chromium.org/chrome/trunk/tools/depot_tools@293192 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Disable Express path for Windows toolchain, and point to instructions

This could be simplified a bunch more, but this path was already
non-functional and tries to download Express which is a waste of
time and confusing for people.

R=dpranke@chromium.org
BUG=433551

Review URL: https://codereview.chromium.org/775733002

git-svn-id: http://src.chromium.org/chrome/trunk/tools/depot_tools@293199 4ff67af0-8c30-449e-8e8b-ad334ec8d88c