Method Lock

tests/gtest/gtest.h:1909–1913

Acquires this mutex.

 public:
  // Acquires this mutex.
  void Lock() {
    GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_lock(&mutex_));
    owner_ = pthread_self();
    has_owner_ = true;
  }

  // Releases this mutex.
  void Unlock() {