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 a1076a99dcf5aa0ac59768c094f6a3d057d3c841..75f32b74621db108b733c857fd9edc36e664fd8c 100644
--- a/content/gpu/gpu_child_thread.cc
+++ b/content/gpu/gpu_child_thread.cc
@@ -60,19 +60,6 @@ namespace {
 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) {
-  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
 // on the IO thread. This allows the UI thread in the browser process to remain
 // fast at all times.
@@ -142,6 +129,18 @@ ChildThreadImpl::Options GetOptions(
 
 }  // namespace
 
+void GpuProcessLogMessageListener::OnMessage(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));
+}
+
 GpuChildThread::GpuChildThread(
     std::unique_ptr<gpu::GpuWatchdogThread> watchdog_thread,
     bool dead_on_arrival,
@@ -195,7 +194,8 @@ GpuChildThread::~GpuChildThread() {
 
 void GpuChildThread::Shutdown() {
   ChildThreadImpl::Shutdown();
-  logging::SetLogMessageHandler(NULL);
+  if (!in_browser_process_)
+    log_listener_.reset();
 }
 
 void GpuChildThread::Init(const base::Time& process_start_time) {
@@ -333,7 +333,7 @@ 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);
+    log_listener_ = base::MakeUnique<GpuProcessLogMessageListener>();
 
   gpu::SyncPointManager* sync_point_manager = nullptr;
   // Note SyncPointManager from ContentGpuClient cannot be owned by this.