Blink-in-JS should not run micro tasks

If Blink-in-JS runs micro tasks, there's a risk of causing a UXSS bug
(see 645211 for concrete steps).

This CL makes Blink-in-JS use callInternalFunction (instead of callFunction)
to avoid running micro tasks after Blink-in-JS' callbacks.

BUG=645211

Review-Url: https://codereview.chromium.org/2330843002
Cr-Commit-Position: refs/heads/master@{#417874}