[scheduler] Bunch of improvements for blink scheduler tracing

third_party/WebKit/public/platform/scheduler/base/task_queue.h

Index: third_party/WebKit/public/platform/scheduler/base/task_queue.h
diff --git a/third_party/WebKit/public/platform/scheduler/base/task_queue.h b/third_party/WebKit/public/platform/scheduler/base/task_queue.h
index 7450d87f9277924f7edf069bf74196e458bf129f..4f48b0024cec6e19689cc5c8f130d600a5ff713e 100644
--- a/third_party/WebKit/public/platform/scheduler/base/task_queue.h
+++ b/third_party/WebKit/public/platform/scheduler/base/task_queue.h
@@ -54,6 +54,9 @@ class BLINK_PLATFORM_EXPORT TaskQueue : public base::SingleThreadTaskRunner {
     FIRST_QUEUE_PRIORITY = CONTROL_PRIORITY,
   };
 
+  // Can be called on any thread.
+  static const char* PriorityToString(QueuePriority priority);
+
   enum class QueueType {
     // Keep TaskQueue::NameForQueueType in sync.
     // This enum is used for a histogram and it should not be re-numbered.