fix(bridge): Synchronize access to Strong handles in collection adapters

[mbektchiev]

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• TNSArrayAdapter, TNSDataAdapter and TNSDictionaryAdapter hold Strong
  references to their underlying JS objects. When the Objective-C instances of these
  classes were dealloc-ed, these references' destructors were being called outside
  of the JSC VM's lock which lead to nasty and rarely occurring crashes when such
  adapters are being used in threads different than the main thread of the JSC engine.

  • Do not store ExecStates as calls to an adapter can be made long after the JS
    state has changed. Use global object's globalExec instead.
  • Reset Strong handles inside the locked section. This way the C++ destructor
    of a nullptr handle will not have to modify anything in the VM's heap.

• Dump the native and JavaScript callstacks when any
  of SIGABRT SIGILL, SIGSEGV, SIGFPE or SIGBUS is received.