Don't use ScopedObjectAccess in Heap::DumpSpaces

ScopedObjectAccess does not work well if the mutator lock is
excusively held while in a suspend thread state. This caused
deadlocks and DCHECK failures.

Bug: 27493316

(cherry picked from commit 03d21bc5bed887243ff6ce3531179185ffd3532c)

Change-Id: I5d67f74fc7082761e45dc1d7778b0ea7fceaaf8f
5 files changed