Fixes for Particles example

- The example is still broken. The cause is 104b6f45a7c366a662582a796a922fde2ec51ad0 (inViewport test does not work for particles)
Fix me.debug.Panel instantiation in all examples
Fix widget rendering in Particle Editor example
Prevent any incorrect object bounding box from ever destroying the globalTranslation buffer.

- Bad bounding boxes contain Infinity or NaN in their position or size
- When a bad bounding box is detected:
  1. The current globalTranslation buffer will be pushed into a stack
  2. The globalTranslation buffer will be clobbered as normal
  3. The clobbered globalTranslation buffer will be used for inViewport tests, as normal
  4. The globalTranslation buffer will be popped from the stack, restoring its original (non-clobbered) state
Fix ParticleContainer bounding box