Make the #includes consistent in various thread checkers between debug and release mode.

Review URL: https://codereview.chromium.org/168373002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251595 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: 587b80e6f3419852606fcbd1f684f0ab834bfd78
diff --git a/base/sequence_checker.h b/base/sequence_checker.h
index 40d535e..ad01828 100644
--- a/base/sequence_checker.h
+++ b/base/sequence_checker.h
@@ -5,8 +5,6 @@
 #ifndef BASE_SEQUENCE_CHECKER_H_
 #define BASE_SEQUENCE_CHECKER_H_
 
-#include "base/memory/ref_counted.h"
-
 // See comments for the similar block in thread_checker.h.
 #if (!defined(NDEBUG) || defined(DCHECK_ALWAYS_ON))
 #define ENABLE_SEQUENCE_CHECKER 1
@@ -14,14 +12,10 @@
 #define ENABLE_SEQUENCE_CHECKER 0
 #endif
 
-#if ENABLE_SEQUENCE_CHECKER
 #include "base/sequence_checker_impl.h"
-#endif
 
 namespace base {
 
-class SequencedTaskRunner;
-
 // Do nothing implementation, for use in release mode.
 //
 // Note: You should almost always use the SequenceChecker class to get
@@ -52,7 +46,7 @@
 //   SequenceChecker sequence_checker_;
 // }
 //
-// In Release mode, CalledOnValidSequence will always return true.
+// In Release mode, CalledOnValidSequencedThread() will always return true.
 #if ENABLE_SEQUENCE_CHECKER
 class SequenceChecker : public SequenceCheckerImpl {
 };