base: Change DCHECK_IS_ON to a macro DCHECK_IS_ON() to match Chromium

changes (see http://crrev.com/e649f573) and fix unit test runtime
errors when building with GYP_DEFINES=dcheck_always_on=1.

include/base/cef_thread_checker.h

@@ -45,25 +45,24 @@
 // If the Chromium implementation diverges the below implementation should be
 // updated to match.
 
+#include "include/base/cef_logging.h"
+#include "include/base/internal/cef_thread_checker_impl.h"
+
 // Apart from debug builds, we also enable the thread checker in
 // builds with DCHECK_ALWAYS_ON so that trybots and waterfall bots
 // with this define will get the same level of thread checking as
 // debug bots.
-//
-// Note that this does not perfectly match situations where DCHECK is
-// enabled.  For example a non-official release build may have
-// DCHECK_ALWAYS_ON undefined (and therefore ThreadChecker would be
-// disabled) but have DCHECKs enabled at runtime.
-#if (!defined(NDEBUG) || defined(DCHECK_ALWAYS_ON))
+#if DCHECK_IS_ON()
 #define ENABLE_THREAD_CHECKER 1
 #else
 #define ENABLE_THREAD_CHECKER 0
 #endif
 
-#include "include/base/internal/cef_thread_checker_impl.h"
 
 namespace base {
 
+namespace cef_internal {
+
 // Do nothing implementation, for use in release mode.
 //
 // Note: You should almost always use the ThreadChecker class to get the
@@ -77,6 +76,8 @@ class ThreadCheckerDoNothing {
   void DetachFromThread() {}
 };
 
+}  // namespace cef_internal
+
 // ThreadChecker is a helper class used to help verify that some methods of a
 // class are called from the same thread. It provides identical functionality to
 // base::NonThreadSafe, but it is meant to be held as a member variable, rather
@@ -109,10 +110,10 @@ class ThreadCheckerDoNothing {
 //
 // In Release mode, CalledOnValidThread will always return true.
 #if ENABLE_THREAD_CHECKER
-class ThreadChecker : public ThreadCheckerImpl {
+class ThreadChecker : public cef_internal::ThreadCheckerImpl {
 };
 #else
-class ThreadChecker : public ThreadCheckerDoNothing {
+class ThreadChecker : public cef_internal::ThreadCheckerDoNothing {
 };
 #endif  // ENABLE_THREAD_CHECKER