For React Native.
-- v3: kernel32/tests: Add tests for RtlActivateActivationContextUnsafe() and RtlDeactivateActivationContextUnsafeFast(). ntdll: Implement RtlDeactivateActivationContextUnsafeFast(). ntdll: Implement RtlActivateActivationContextUnsafeFast(). ntdll: Set and check 0x8 flag for activation context stack frames. kernel32/tests: Add tests for normal activation context stack frame flags. ntdll: Use explicit ACTIVATION_CONTEXT type instead of HANDLE.