Propagate proper FROM_HERE to postTask() in worker code
Some of postTask() implementation in Worker code don't have
WebTraceLocation parameter, and pass wrong FROM_HEREs. That
make it hard to follow the call stack in a crash report.
This adds the missing WebTraceLocation parameter, puts correct
FROM_HEREs and adds alias() to ensure it's in the crash report.
Committed:
https://crrev.com/c58cf271a13e03259fe3e6ed5c200041b25a703c
Cr-Commit-Position: refs/heads/master@{#408886}