Fix compatibility with Rails 4 browser error reporting

Rails 4 has introduced a new way of code extraction for browser error
reporting.

If a syntax error occurred in template, we should prepend to the
backtrace template's filename and line.

Also, extend syntax error tests to the introduced case.
better version of #527

closes #527
Revert "better version of #527"

This reverts commit d569e238fbe8ac78e891657d6f5cfe226309a03c.
Merge remote-tracking branch 'zof/error-reporting'
Parser: Add comment about backtrace manipulation