Bug 1022891 - Part 1: Fix IonBailoutIterator for non-top frames.
Bug 1022891 - Part 2: Teach IonBailoutIterator about PJS scripts.
Bug 1022891 - Part 3: Fix instantiating InlineFrameIterator from inside InlineFrameIterator when settled on a bailout frame.
Bug 1019304 - Part 1: Teach RematerializedFrame to rematerialize bailout frames.
Bug 1019304 - Part 2: Overhaul PJS bailout mechanism to be like the normal bailout mechanism.

- Remove ad-hoc IR tracing and AbortPar machinery.
- PJS bailouts use a different handler that unwinds the entire ForkJoin
  stack, but otherwise shares the same code as sequential bailouts.
- Each thread's stack is snapshotted as a RematerializedFrame vector.