Merge "Expose systemReady for SystemServer" am: 33737f6ac4 am: 7d2c52067f am: 91ee69fca8

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1640142

Change-Id: I95488b39a32ed9086839eab6c457ed6f75472df1
tree: ba65c8fe74294f54c6117a1dbee4af3fcf81ca75
  1. core/
  2. framework/
  3. service/
  4. services/
  5. tests/
  6. OWNERS