[MERGE #1571 @leirocks] Fix assertion on recovering the protection of unusable pages when failed to add it to block map (8398465)
[MERGE #1571 @leirocks] Fix assertion on recovering the protection of unusable pages when failed to add it to block map (8398465)

Merge pull request #1571 from leirocks:unusablepages

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