Make it faster and correcter.
Also, fixed the "gen" script to update the static/egl/*.java files
as part of doing an update. Altered the "git" lines to change
directories before invoking git -- necessary because we're now
split between frameworks/base and frameworks/native.
Bug 9204146
Change-Id: Ie60504b1932349e6f2c9d3868dee6a645ef2b36e