This will let DEPS files specify a higher local bound for recursion.
Note there is an edge case where a dependency can be initially pulled
in with a lower recursion level and then gets ignored subsequently
when a lower level DEPS overrides it's inclusion level and then
includes the same dependency.  I do not solve this case, as
I am intending to use this syntax for top level deps files.

BUG=155780


Review URL: https://chromiumcodereview.appspot.com/11146032

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@162464 0039d316-1c4b-4281-b951-d872f2087c98