Fix wrapper equals()

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