Request Picker task

components/offline_pages/core/task_queue.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/offline_pages/core/task_queue.h"
 
 #include "base/bind.h"
 #include "base/threading/thread_task_runner_handle.h"
 
 namespace offline_pages {
@@ skipping 12 matching lines @@
 
 bool TaskQueue::HasPendingTasks() const {
   return !tasks_.empty() || HasRunningTask();
 }
 
 bool TaskQueue::HasRunningTask() const {
   return current_task_.get() != nullptr;
 }
 
 void TaskQueue::MaybeStartTask() {
+  DVLOG(2) << "running? " << HasRunningTask() << ", pending? "

[fgorski, 2016/11/09 17:58:07]

is this needed?

[Pete Williamson, 2016/11/09 23:53:56]

Yes.  I've added it about 5 times while debugging, which normally tells me we
need a permanent log statement.  It is level 2, so it will be out of our face
almost all the time, but when I did have a  problem with a task not starting,
this was almost always the line that let me know the problem.

+           << HasPendingTasks() << " " << __func__;
   if (HasRunningTask() || !HasPendingTasks())
     return;
 
   current_task_ = std::move(tasks_.front());
   tasks_.pop();
   current_task_->Run();
 }
 
 void TaskQueue::TaskCompleted(Task* task) {
   DCHECK_EQ(task, current_task_.get());
   if (task == current_task_.get()) {
     current_task_.reset(nullptr);
     MaybeStartTask();
   }
 }
 
 }  // namespace offline_pages