[blink] Split TaskType::Internal into InternalTimer and InternalLoading.

third_party/WebKit/Source/core/dom/TaskRunnerHelper.h

 // 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.
 
 #ifndef TaskRunnerHelper_h
 #define TaskRunnerHelper_h
 
 #include "core/CoreExport.h"
 #include "wtf/Allocator.h"
 #include "wtf/HashTraits.h"
@@ skipping 19 matching lines @@
   Microtask,
   Timer,
   RemoteEvent,
   WebSocket,
   PostedMessage,
   UnshippedPortMessage,
 
   // Other internal tasks that cannot fit any of the above task runners
   // can be posted here, but the usage is not encouraged. The task runner
   // may be throttled.
-  Internal,
+  //
+  // InternalLoading should be related to loading tasks, which can cause
+  // regressions in page load time when throttled in the background.

[Sami, 2016/12/08 17:05:08]

I think this is worded a bit too negatively. Maybe just say for tasks that are
associated with loading page content?

[altimin, 2016/12/08 17:47:40]

Done.

+  // InternalTimer should be used for all other purposes.
+  InternalTimer,
+  InternalLoading,
 
   // Tasks that must not be throttled should be posted here, but the usage
   // should be very limited.
   Unthrottled,
 
   // Tasks that any other TaskType is not assigned to. This should be
   // transitional and should be removed.
   Unspecified,
 };
 
@@ skipping 15 matching lines @@
  public:
   static WebTaskRunner* get(TaskType, LocalFrame*);
   static WebTaskRunner* get(TaskType, Document*);
   static WebTaskRunner* get(TaskType, ExecutionContext*);
   static WebTaskRunner* get(TaskType, ScriptState*);
 };
 
 }  // namespace blink
 
 #endif