diff --git a/webrtc/base/thread_checker_impl.cc b/webrtc/base/thread_checker_impl.cc
index 5e4aab8e32..5d59c99c10 100644
--- a/webrtc/base/thread_checker_impl.cc
+++ b/webrtc/base/thread_checker_impl.cc
@@ -25,8 +25,6 @@ PlatformThreadId CurrentThreadId() {
 #if defined(WEBRTC_WIN)
   ret = GetCurrentThreadId();
 #elif defined(WEBRTC_POSIX)
-  // Pthreads doesn't have the concept of a thread ID, so we have to reach down
-  // into the kernel.
 #if defined(WEBRTC_MAC) || defined(WEBRTC_IOS)
   ret = pthread_mach_thread_np(pthread_self());
 #elif defined(WEBRTC_LINUX)
@@ -42,30 +40,34 @@ PlatformThreadId CurrentThreadId() {
   return ret;
 }
 
-ThreadCheckerImpl::ThreadCheckerImpl() : valid_thread_(CurrentThreadId()) {
+PlatformThreadRef CurrentThreadRef() {
+#if defined(WEBRTC_WIN)
+  return GetCurrentThreadId();
+#elif defined(WEBRTC_POSIX)
+  return pthread_self();
+#endif
+}
+
+bool IsThreadRefEqual(const PlatformThreadRef& a, const PlatformThreadRef& b) {
+#if defined(WEBRTC_WIN)
+  return a == b;
+#elif defined(WEBRTC_POSIX)
+  return pthread_equal(a, b);
+#endif
+}
+
+ThreadCheckerImpl::ThreadCheckerImpl() : valid_thread_(CurrentThreadRef()) {
 }
 
 ThreadCheckerImpl::~ThreadCheckerImpl() {
 }
 
 bool ThreadCheckerImpl::CalledOnValidThread() const {
-  const PlatformThreadId current_thread = CurrentThreadId();
+  const PlatformThreadRef current_thread = CurrentThreadRef();
   CritScope scoped_lock(&lock_);
   if (!valid_thread_)  // Set if previously detached.
     valid_thread_ = current_thread;
-#if defined(WEBRTC_MAC) || defined(WEBRTC_IOS)
-  // TODO(tommi): Remove this hack after we've figured out the roll issue
-  // with chromium's Mac 10.9 debug bot.
-  if (valid_thread_ != current_thread) {
-    // At the moment, this file cannot use logging from either webrtc or
-    // libjingle. :(
-    fprintf(stderr, "*** WRONG THREAD *** current=%i vs valid=%i\n",
-        current_thread, valid_thread_);
-  }
-  return true;  // le sigh.
-#else
-  return valid_thread_ == current_thread;
-#endif
+  return IsThreadRefEqual(valid_thread_, current_thread);
 }
 
 void ThreadCheckerImpl::DetachFromThread() {
diff --git a/webrtc/base/thread_checker_impl.h b/webrtc/base/thread_checker_impl.h
index 67adc6ebdf..5ad15bb515 100644
--- a/webrtc/base/thread_checker_impl.h
+++ b/webrtc/base/thread_checker_impl.h
@@ -25,12 +25,18 @@ namespace rtc {
 // Used for identifying the current thread. Always an integer value.
 #if defined(WEBRTC_WIN)
 typedef DWORD PlatformThreadId;
+typedef DWORD PlatformThreadRef;
 #elif defined(WEBRTC_POSIX)
 typedef pid_t PlatformThreadId;
+typedef pthread_t PlatformThreadRef;
 #endif
 
 // TODO(tommi): This+PlatformThreadId belongs in a common thread related header.
 PlatformThreadId CurrentThreadId();
+PlatformThreadRef CurrentThreadRef();
+
+// Compares two thread identifiers for equality.
+bool IsThreadRefEqual(const PlatformThreadRef& a, const PlatformThreadRef& b);
 
 // Real implementation of ThreadChecker, for use in debug mode, or
 // for temporary use in release mode (e.g. to CHECK on a threading issue
@@ -54,7 +60,7 @@ class ThreadCheckerImpl {
   mutable CriticalSection lock_;
   // This is mutable so that CalledOnValidThread can set it.
   // It's guarded by |lock_|.
-  mutable PlatformThreadId valid_thread_;
+  mutable PlatformThreadRef valid_thread_;
 };
 
 }  // namespace rtc
diff --git a/webrtc/base/thread_checker_unittest.cc b/webrtc/base/thread_checker_unittest.cc
index 762fad20c0..03053ad02e 100644
--- a/webrtc/base/thread_checker_unittest.cc
+++ b/webrtc/base/thread_checker_unittest.cc
@@ -157,15 +157,7 @@ void ThreadCheckerClass::MethodOnDifferentThreadImpl() {
 }
 
 #if ENABLE_THREAD_CHECKER
-// TODO(tommi): Re-enable tests after figuring out issue with Chromium try bots.
-#if defined(WEBRTC_MAC) || defined(WEBRTC_IOS)
-#define MAYBE_MethodNotAllowedOnDifferentThreadInDebug \
-    DISABLED_MethodNotAllowedOnDifferentThreadInDebug
-#else
-#define MAYBE_MethodNotAllowedOnDifferentThreadInDebug \
-    MethodNotAllowedOnDifferentThreadInDebug
-#endif
-TEST(ThreadCheckerDeathTest, MAYBE_MethodNotAllowedOnDifferentThreadInDebug) {
+TEST(ThreadCheckerDeathTest, MethodNotAllowedOnDifferentThreadInDebug) {
   ASSERT_DEATH({
       ThreadCheckerClass::MethodOnDifferentThreadImpl();
     }, "");
@@ -194,13 +186,7 @@ void ThreadCheckerClass::DetachThenCallFromDifferentThreadImpl() {
 }
 
 #if ENABLE_THREAD_CHECKER
-// TODO(tommi): Re-enable tests after figuring out issue with Chromium try bots.
-#if defined(WEBRTC_MAC) || defined(WEBRTC_IOS)
-#define MAYBE_DetachFromThreadInDebug DISABLED_DetachFromThreadInDebug
-#else
-#define MAYBE_DetachFromThreadInDebug DetachFromThreadInDebug
-#endif
-TEST(ThreadCheckerDeathTest, MAYBE_DetachFromThreadInDebug) {
+TEST(ThreadCheckerDeathTest, DetachFromThreadInDebug) {
   ASSERT_DEATH({
     ThreadCheckerClass::DetachThenCallFromDifferentThreadImpl();
     }, "");