AdjustLiveBytes and friends takes a heap object pointer instead of an address.

AdjustLiveBytes and friends takes a heap object pointer instead of an address.

That makes going to the page safe. Addresses can be in arbitrary locations of an object, e.g. in a large object but not on the first 1M page.
BUG=

Review URL: https://codereview.chromium.org/1256203004

Cr-Commit-Position: refs/heads/master@{#29991}