The change is partial to keep this change still correct but readable/reviewable.
Followup changes will further move functions into the Dependency class.
If it was done in one change, it would be unreviewable.
Fix GetScmName() for protocol svn+ssh://.

TEST=didn't break the smoke tests.

Review URL: http://codereview.chromium.org/2837001

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@49707 0039d316-1c4b-4281-b951-d872f2087c98