This API is used by Blink to inform V8 about HTML frames being disposed.
Using the optional parameter, Blink can tell V8 whether the disposed
frame was a main frame. In that case, we might want to reset GC
parameters

BUG=none
R=hpayer@chromium.org
LOG=y

Review URL: https://codereview.chromium.org/823583003

Cr-Commit-Position: refs/heads/master@{#25926}