[DevTools] Disallow use of global properties "document", "addEventListener" and "removeEventListener".

BUG=424188

Review URL: https://codereview.chromium.org/659973003

git-svn-id: svn://svn.chromium.org/blink/trunk@184164 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: ignore weak referenced when calculating dominators for heap snapshot

Oherwise retained size of an object would be affected by the references.

BUG=425905

Review URL: https://codereview.chromium.org/674443003

git-svn-id: svn://svn.chromium.org/blink/trunk@184165 bbb929c8-8fbe-4397-9dbb-9b2b20218538