support multiple log message handlers in base/logging.h

base/logging_win.h

Index: base/logging_win.h
diff --git a/base/logging_win.h b/base/logging_win.h
index cdde7bb687cbbd524a0b5e412e0a2c6714b06f3f..aab7898216b16c6e07db37e12c0407feae9480c1 100644
--- a/base/logging_win.h
+++ b/base/logging_win.h
@@ -57,8 +57,10 @@ class BASE_EXPORT LogEventProvider : public base::win::EtwTraceProvider {
  public:
   static LogEventProvider* GetInstance();
 
-  static bool LogMessage(logging::LogSeverity severity, const char* file,
-      int line, size_t message_start, const std::string& str);
+  static bool LogMessage(logging::LogSeverity severity,
+                         const std::string& file,
+                         int line,
+                         const std::string& str);
 
   static void Initialize(const GUID& provider_name);
   static void Uninitialize();