Make sure to begin paths when building clip rects.
Merge pull request #1411 from tschneidereit/nat

Memory optimizations/ leak fixes
Show multiple backends side by side in the inspector.
Merge branch 'nat' of https://github.com/mozilla/shumway into nat
Merge pull request #1417 from mbebenita/nat

Show multiple backends side by side in the inspector.
Only collect timeline profiles when the profiler is active.
Merge pull request #1418 from mbebenita/nat

Only collect timeline profiles when the profiler is active.
Cleanup
Correct guard in Shumway.Player.leaveTimeline
Lazily create backing buffers in Shumway.Tools.Profiler.TimelineBuffer

Prevents allocation of more than 48MB during startup.