Add the error name and error message in Firefox error reports.

Chrome gives the error name and error message in the stack trace already.

Also, no need to check `if stack` since we already filter them.
Faster Post::parseQuotes

What changed is about 3~4 times faster now.
Resulting code is also less complex.
Faster Post::parseQuotes

What changed is 4~6 times faster.
Factor Post::parseQuote out of Post::parseQuotes
Merge branch 'v3' into watcher