Rename BASE_API to BASE_EXPORT.

base/threading/thread_checker_impl.h

Index: base/threading/thread_checker_impl.h
===================================================================
--- base/threading/thread_checker_impl.h	(revision 95578)
+++ base/threading/thread_checker_impl.h	(working copy)
@@ -6,7 +6,7 @@
 #define BASE_THREADING_THREAD_CHECKER_IMPL_H_
 #pragma once
 
-#include "base/base_api.h"
+#include "base/base_export.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/platform_thread.h"
 
@@ -18,7 +18,7 @@
 //
 // Note: You should almost always use the ThreadChecker class to get the
 // right version for your build configuration.
-class BASE_API ThreadCheckerImpl {
+class BASE_EXPORT ThreadCheckerImpl {
  public:
   ThreadCheckerImpl();
   ~ThreadCheckerImpl();