Revert "Bug 845487 - Dialer responds to cross-origin messages without verifying the source (exploitable)."

This reverts commit 7e0e1b8925214718c400dcdecbe680c8c64b68d8.
Merge pull request #8734 from KevinGrandon/fix_lint_errors

Revert "Bug 845487 - Dialer responds to cross-origin messages without verifying the source (exploitable)."