Track libcore DirectByteBuffer cleanup.

Bug: https://code.google.com/p/android/issues/detail?id=53637
Change-Id: I7acd990a2a48b41dacb5b09f6410b4634dd60438
Track 64-bit nio changes.

Change-Id: Id7a11af5f94b8ba82d42e1e7045302aca533f31a
Track libcore's DirectByteBuffer <init> change.

See 9ce6a2533b50ffcd24b8b10bae7f234042768819.

Change-Id: Ie736e69a3fa7bdf55709d8e2960761202a20e820
Fix a cast in JniEnv::NewDirectByteBuffer.

Change-Id: I8692b31c6ce64efc68124df02117b6e4529dfe98