Revert "Additional checks in GetDirectBuffer{Address,Capacity}"

This reverts commit d0638fad2d5bb0d044bb4f4e19224cda298ddf21.

Reason for revert: Breaks GetDirectBufferCapacity() for zero sized direct buffers created via FileChannel.map().

Bug: 122025675
Change-Id: I54d696b39c4ef8e288c10e96fe3d5997458efb53
Test: art/tools/buildbuild-build.sh --host && jni_internal_test
4 files changed