Bug 867757 - Part 1: Allow markers to carry payload. r=aklotz

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extra : rebase_source : 31904aa5f084283bfc23ecfc53762d275967e34b
Bug 918581 - Extend merge-profile.py to support secondary threads. r=vlad

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extra : rebase_source : 28357bbb17b15c7cb40c53ee3442bc6366fcf015
Bug 903569.  Remove the unneeded CheckPropertyAccess call in the GSP.  r=bholley,peterv
Bug 917539.  Move the JSCompartment argument to the end of the list for JS-implemented WebIDL, so C++ callers can call into it sanely too.  r=peterv
Bug 917958 part 1.  Stop using JSObject* to represent WebIDL callback functions in workers.  r=smaug
Bug 917958 part 2.  Simplify our various typeNeedsCx stuff, now that it's the same on workers and mainthread.  r=smaug