Add LockedContext
WIP: Parallel VM call frame
Tag parallel callee tokens
Get basic property ICs working
reduce size of the arrays to lower test running time
force sequential in non-thread-safe builds
Fix bailout on map-nested

The bug is interesting. What happens is that somewhere along the line
heuristics were changed and we were hitting OSR'd Ion code where Ion didn't
kick in before. In the compiled loop, we inlined NewParallelArray into a call
to the custom init function, ParallelArrayView. This function returns void, so
the InvokeFunction VMFunction recorded void in the typeset of the call.
Merge branch 'pvm'