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

content/gpu/gpu_child_thread.cc

Index: content/gpu/gpu_child_thread.cc
diff --git a/content/gpu/gpu_child_thread.cc b/content/gpu/gpu_child_thread.cc
index af207abecc83bbbb6b4f90ae422748405757120e..13d1e2c658eaff42f75b926a321b70e7e4ff072b 100644
--- a/content/gpu/gpu_child_thread.cc
+++ b/content/gpu/gpu_child_thread.cc
@@ -61,17 +61,15 @@ base::LazyInstance<base::ThreadLocalPointer<GpuChildThread>> g_lazy_tls =
 static base::LazyInstance<scoped_refptr<ThreadSafeSender> >
     g_thread_safe_sender = LAZY_INSTANCE_INITIALIZER;
 
-bool GpuProcessLogMessageHandler(int severity,
-                                 const char* file, int line,
-                                 size_t message_start,
-                                 const std::string& str) {
+void GpuProcessLogMessageListener(int severity,
+                                  const char* file, int line,
+                                  size_t message_start,
+                                  const std::string& str) {
   std::string header = str.substr(0, message_start);
   std::string message = str.substr(message_start);
 
   g_thread_safe_sender.Get()->Send(
       new GpuHostMsg_OnLogMessage(severity, header, message));
-
-  return false;
 }
 
 // Message filter used to to handle GpuMsg_CreateGpuMemoryBuffer messages
@@ -205,7 +203,8 @@ GpuChildThread::~GpuChildThread() {
 
 void GpuChildThread::Shutdown() {
   ChildThreadImpl::Shutdown();
-  logging::SetLogMessageHandler(NULL);
+  if (!in_browser_process_)
+    logging::RemoveLogMessageListener(GpuProcessLogMessageListener);
 }
 
 void GpuChildThread::Init(const base::Time& process_start_time) {
@@ -395,7 +394,7 @@ void GpuChildThread::OnInitialize(const gpu::GpuPreferences& gpu_preferences) {
   // We don't need to pipe log messages if we are running the GPU thread in
   // the browser process.
   if (!in_browser_process_)
-    logging::SetLogMessageHandler(GpuProcessLogMessageHandler);
+    logging::AddLogMessageListener(GpuProcessLogMessageListener);
 
   gpu::SyncPointManager* sync_point_manager = nullptr;
   // Note SyncPointManager from ContentGpuClient cannot be owned by this.