Bug 958782 - 1/3: B2G SMS - Move MozMobileMessage to WebIDL. XPIDL & WebIDL changes. f=Ms2ger,r=khuey

--HG--
rename : dom/webidl/MobileMessageManager.webidl => dom/webidl/MozMobileMessageManager.webidl
Bug 958782 - 2.a/3: refactoring, alignments. f=Ms2ger,r=khuey
Bug 958782 - 2.b/3: WebIDL implementation. f=Ms2ger,bzbarsky,r=khuey
Bug 958782 - 2.c/3: remove unused headers and sort. r=khuey
Bug 958782 - 3/3: fix test cases. r=gene,khuey
Bug 993817: convert mobilemssage marionette test cases to Promise. r=gene
Bug 1002600: fix test_mms_pdu_helper.js intermittent timeouts. r=gene
Bug 992320: split test_wsp_pdu_helper.js for intermittent timeout. r=gene