Don't process UEvents in Dalvik unless they match a pattern.

On some devices, vsync is delivered from the kernel to userspace
over a netlink socket via UEvent.  The result is that a thread wakes
up, reads a message, creates a new String then searches it for matches
against a pattern on every single frame.

Reduce the overhead by performing the initial pattern matching in
native code.

Bug: 7326329
Change-Id: Icb22db1c38330694207bec1153840e0c06f502d6