Revert "Use the card table to scan the immune region of the heap."

This reverts commit 6c355e53332502314c3d82a7afcf898d66118f27.

Conflicts are resolved in:

	vm/alloc/CardTable.cpp
	vm/alloc/HeapBitmap.cpp
	vm/alloc/HeapInternal.h
	vm/alloc/HeapSource.cpp
	vm/alloc/MarkSweep.cpp

Tested with overnight monkey runs + Delaunay.

Bug: 5037417
Change-Id: I400eff8542d0bddd865ce570a479f7750c1ba484
9 files changed