[Try # 3] Scheduler refactoring to virtually eliminate redundant DoWorks

third_party/WebKit/Source/platform/scheduler/base/task_queue_selector.cc

Index: third_party/WebKit/Source/platform/scheduler/base/task_queue_selector.cc
diff --git a/third_party/WebKit/Source/platform/scheduler/base/task_queue_selector.cc b/third_party/WebKit/Source/platform/scheduler/base/task_queue_selector.cc
index d7c5c297dc55d40a2499d483b0d382a3ea604c96..0a24636c20c8082417c45cf28ef6cf86e92ab559 100644
--- a/third_party/WebKit/Source/platform/scheduler/base/task_queue_selector.cc
+++ b/third_party/WebKit/Source/platform/scheduler/base/task_queue_selector.cc
@@ -163,12 +163,14 @@ bool TaskQueueSelector::PrioritizingSelector::
         WorkQueue** out_work_queue) const {
   WorkQueue* immediate_queue;
   DCHECK_EQ(*out_chose_delayed_over_immediate, false);
-  if (immediate_work_queue_sets_.GetOldestQueueInSet(priority,
-                                                     &immediate_queue)) {
+  EnqueueOrder immediate_enqueue_order;
+  if (immediate_work_queue_sets_.GetOldestQueueAndEnqueueOrderInSet(
+          priority, &immediate_queue, &immediate_enqueue_order)) {
     WorkQueue* delayed_queue;
-    if (delayed_work_queue_sets_.GetOldestQueueInSet(priority,
-                                                     &delayed_queue)) {
-      if (immediate_queue->ShouldRunBefore(delayed_queue)) {
+    EnqueueOrder delayed_enqueue_order;
+    if (delayed_work_queue_sets_.GetOldestQueueAndEnqueueOrderInSet(
+            priority, &delayed_queue, &delayed_enqueue_order)) {
+      if (immediate_enqueue_order < delayed_enqueue_order) {
         *out_work_queue = immediate_queue;
       } else {
         *out_chose_delayed_over_immediate = true;
@@ -189,13 +191,9 @@ bool TaskQueueSelector::PrioritizingSelector::ChooseOldestWithPriority(
   // Select an immediate work queue if we are starving immediate tasks.
   if (task_queue_selector_->immediate_starvation_count_ >=
       kMaxDelayedStarvationTasks) {
-    if (ChooseOldestImmediateTaskWithPriority(priority, out_work_queue)) {
+    if (ChooseOldestImmediateTaskWithPriority(priority, out_work_queue))
       return true;
-    }
-    if (ChooseOldestDelayedTaskWithPriority(priority, out_work_queue)) {
-      return true;
-    }
-    return false;
+    return ChooseOldestDelayedTaskWithPriority(priority, out_work_queue);
   }
   return ChooseOldestImmediateOrDelayedTaskWithPriority(
       priority, out_chose_delayed_over_immediate, out_work_queue);