Parcel: noop upon double recycle

Fix this scenario:

  Parcel p = Parcel.obtain();
  p.recycle();
  p.recycle(); // illegal but possible

  Parcel p1 = Parcel.obtain();
  Parcel p2 = Parcel.obtain();

  ASSERT_TRUE(p1 != p2); // fail!

Signed-off-by: Jintao Zhu <zhu.jintao@gm.com>

Change-Id: Ied25188549801122874a05c2e66969e1f281b346