Refactor HWUI to better handle Canvas DrawFilters.

First, this CL removes the need to decompose the DrawFilters
in Java and instead passes the SkDrawFilter to HWUI directly.
This also allows the removal of duplicated logic between HWUI
and other Canvas implementations regarding Paint filter levels.

Second, the DrawFilter is now stored in the DisplayListRenderer
where we apply it to every paint BEFORE it is stored in the
DisplayList.  This eliminates the need to filter all Paints on
playback and removes additional complexity at playback.

Finally, as a result of storing the filtered paint we can now
do a better job caching the paints.  This takes advantage of
recent changes in Skia to quickly enable quick hashing and
comparison of paint objects.

Change-Id: Iec507a2d894827975cc4f1d22241542bb0534b4e