Merge pull request #9410 from gnarf37/845173

Bug 845173 - [MMS][Utility] Convert HTML element to mms SMIL and vise versa. r=julien(cherry picked from commit ab0d1173cb6d3eb98b7a75e4d1feaa1846216612)

Conflicts:
	apps/sms/test/unit/utils_test.js