Issue 881875 tracks adding minimal annotations to base::Lock and base::AutoLock that would enable adding GUARDED_BY annotations and enforcements for fields protected by base::AutoLock.  Such minimal annotations are insufficient for

1. base::AutoLock(..., base::AutoLock::AlreadyAcquired()) constructor which will trigger compiler errors until base::Lock::Try is annotated with EXCLUSIVE_TRYLOCK_FUNCTION.

2. Analysing and enforcing direct usage of base::Lock methods.


Let's use this bug to track annotating Lock methods as follows:

  void Acquire() EXCLUSIVE_LOCK_FUNCTION();
  void Release() UNLOCK_FUNCTION();
  bool Try() EXCLUSIVE_TRYLOCK_FUNCTION(true);
  void AssertAcquired() const ASSERT_EXCLUSIVE_LOCK();