Bug 743436 - remove XPCJSRuntime::mJSCycleCollectionContext and related code. r=peterv

The patch removes no longer used XPCJSRuntime::mJSCycleCollectionContext,
nsXPConnect::mCycleCollectionContext and related code to create/destroy
contexts. As that made nsCycleCollectionJSRuntime::FinishTraverse() empty
in all cases I removed that method as well.
Bug 846955 - Codegen Argument definitions using .define() in ClassDestructor::define. r=bz
Bug 847000 - JSMSG_CANT_CONVERT_TO mapped to 35_TO in self-hosted code. r=tschneidereit

--HG--
extra : rebase_source : 5a8bc53c47b45c8ff288a3859601a5476e2901e9
No bug, Automated blocklist update from host bld-linux64-ec2-634 - a=blocklist-update
Backout part of Bug 812179 for SeaMonkey bustage. rs+=gps
Merge central to inbound
Bug 833403 - Integrate libwebvtt into Mozilla. r=ted

 - Updated for new build system (2/28/2013)
 - declaration-after-statement no longer breaking MSVC build
 - Source files and scripts now contain appropriate license info
 - media/webvtt/update.sh no longer hiding unexpected/significant
   errors.