[MERGE #2841 @leirocks] fix possible memory leak
[MERGE #2841 @leirocks] fix possible memory leak

Merge pull request #2841 from leirocks:fbcleanup

while shutting down I assume there's no need to cleanup the pointers.
however there can be a situation with dynamic profile input, constant
table can hold a reference to a pinned var(like ImageData/typedarray)
causes two pinned object on a circle and lead to memory leak.
the circle is like this:

pinned typedArray(ImageData in my case, from another scriptContext)->type->
javascriptLibrary(pinned through global object)->
cache->sourceContextInfoMap->sourceDynamicProfileManager->
dynamicProfileInfoMap->functionBody(for global function)->
constTable[x](crossSite global object)->auxAlots[x] (CEO)->auxSlots[x] (typedArray(circle))

with change #2825 the constTable is not cleaned up while another scriptContext were forcibly closed and kept the above circle

also make better clean up -- just set auxPtrs to nullptr instead of updating each of them

Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore