Allow multiple logging::LogMessage{Handler,Listener}s

components/crash/content/app/breakpad_mac.mm

Index: components/crash/content/app/breakpad_mac.mm
diff --git a/components/crash/content/app/breakpad_mac.mm b/components/crash/content/app/breakpad_mac.mm
index d7ab1ae6389a1a36759d3b637a767d33f13a188d..1a13b200ebbd44c37097e8bb6e210032e64f9ef9 100644
--- a/components/crash/content/app/breakpad_mac.mm
+++ b/components/crash/content/app/breakpad_mac.mm
@@ -73,11 +73,22 @@ void ClearCrashKeyValueImpl(const base::StringPiece& key) {
   }
 }
 
-bool FatalMessageHandler(int severity, const char* file, int line,
-                         size_t message_start, const std::string& str) {
+class FatalMessageListener : logging::LogMessageListener {
+  void OnMessage(int severity,
+                 const char* file,
+                 int line,
+                 size_t message_start,
+                 const std::string& str) override;
+};
+
+void FatalMessageListener::OnMessage(int severity,
+                                     const char* file,
+                                     int line,
+                                     size_t message_start,
+                                     const std::string& str) {
   // Do not handle non-FATAL.
   if (severity != logging::LOG_FATAL)
-    return false;
+    return;
 
   // In case of OOM condition, this code could be reentered when
   // constructing and storing the key.  Using a static is not
@@ -85,7 +96,7 @@ bool FatalMessageHandler(int severity, const char* file, int line,
   // fatal crash at the same time, this should work.
   static bool guarded = false;
   if (guarded)
-    return false;
+    return;
 
   base::AutoReset<bool> guard(&guarded, true);
 
@@ -104,7 +115,7 @@ bool FatalMessageHandler(int severity, const char* file, int line,
 
   // Rather than including the code to force the crash here, allow the
   // caller to do it.
-  return false;
+  return;
 }
 
 // BreakpadGenerateAndSendReport() does not report the current
@@ -264,7 +275,9 @@ void InitCrashReporter(const std::string& process_type) {
   SetCrashKeyValue(@"prod", [info_dictionary objectForKey:@BREAKPAD_PRODUCT]);
   SetCrashKeyValue(@"plat", @"OS X");
 
-  logging::SetLogMessageHandler(&FatalMessageHandler);
+  // Intentionally leak the listener.
+  new FatalMessageListener();
+
   base::debug::SetDumpWithoutCrashingFunction(&DumpHelper::DumpWithoutCrashing);
 
   // abort() sends SIGABRT, which breakpad does not intercept.