Move allocation profiler out of experiment

It is replaced with a checkbox on the Settings panel called "Record heap allocation stack traces". When that checkbox is ticked "Record heap allocations" profile will also record allocation stack traces.

BUG=277984

Review URL: https://codereview.chromium.org/348893005

git-svn-id: svn://svn.chromium.org/blink/trunk@176974 bbb929c8-8fbe-4397-9dbb-9b2b20218538