Ambient Shadow implemented

This diff adds ambient shadows to the high quality shadow painter. It
modifies some of the existing math classes to compensate the new format
of drawing as well as the buffer for triangle.

Bugs: 72445494
Test: Screenshot test modified

Change-Id: I6dcf2b56bc3408712d0d46251494a1a407561255
(cherry picked from commit 3e513882f62c0870d8def5cc87fc37abbfa5d90f)