Revert "Revert "Improve the thread flip.""

Revert "Revert "Improve the thread flip.""

This reverts commit db3204f87c3f7c4de89762ce9e8502a9dc25c2d8.

Improve the thread flip.

- In addition to the threads that are suspended in FullSuspendCheck(),
  prioritize the resume of threads that are blocking for the thread
  flip at the JNI critical section entry and threads are about to
  transition to runnable (eg. blocking at the SOA entry from JNI).
- Shorten the length of the thread flip critical
  section (ThreadFlipBegin/End).
- Add some systrace scopes.
- Add a read barrier for the locked objects during the thread dump in
  case the thread is in the middle of flipping.

Bug: 30980189
Bug: 29517059
Bug: 12687968
Test: test-art-host, Ritz EAAC, N9 libartd boot
Change-Id: I3a903c47c0fcc746664ec376cc31dee8af3c3ecb