scheduler: Move the Blink scheduler into Blink

components/scheduler/renderer/renderer_scheduler.h

-// Copyright 2014 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 COMPONENTS_SCHEDULER_RENDERER_RENDERER_SCHEDULER_H_
-#define COMPONENTS_SCHEDULER_RENDERER_RENDERER_SCHEDULER_H_
-
-#include <memory>
-
-#include "base/macros.h"
-#include "base/message_loop/message_loop.h"
-#include "components/scheduler/child/child_scheduler.h"
-#include "components/scheduler/child/single_thread_idle_task_runner.h"
-#include "components/scheduler/renderer/render_widget_scheduling_state.h"
-#include "components/scheduler/scheduler_export.h"
-#include "third_party/WebKit/public/platform/WebScheduler.h"
-#include "third_party/WebKit/public/web/WebInputEvent.h"
-#include "v8/include/v8.h"
-
-namespace base {
-namespace trace_event {
-class BlameContext;
-}
-}
-
-namespace cc {
-struct BeginFrameArgs;
-}
-
-namespace blink {
-class WebLocalFrame;
-class WebThread;
-}
-
-namespace scheduler {
-
-class RenderWidgetSchedulingState;
-
-class SCHEDULER_EXPORT RendererScheduler : public ChildScheduler {
- public:
-  class SCHEDULER_EXPORT RAILModeObserver {
-   public:
-    virtual ~RAILModeObserver();
-    virtual void OnRAILModeChanged(v8::RAILMode rail_mode) = 0;
-  };
-
-  ~RendererScheduler() override;
-  static std::unique_ptr<RendererScheduler> Create();
-
-  // Returns the compositor task runner.
-  virtual scoped_refptr<TaskQueue> CompositorTaskRunner() = 0;
-
-  // Creates a WebThread implementation for the renderer main thread.
-  virtual std::unique_ptr<blink::WebThread> CreateMainThread() = 0;
-
-  // Returns the loading task runner.  This queue is intended for tasks related
-  // to resource dispatch, foreground HTML parsing, etc...
-  virtual scoped_refptr<TaskQueue> LoadingTaskRunner() = 0;
-
-  // Returns the timer task runner.  This queue is intended for DOM Timers.
-  // TODO(alexclarke): Get rid of this default timer queue.
-  virtual scoped_refptr<TaskQueue> TimerTaskRunner() = 0;
-
-  // Returns a new loading task runner. This queue is intended for tasks related
-  // to resource dispatch, foreground HTML parsing, etc...
-  virtual scoped_refptr<TaskQueue> NewLoadingTaskRunner(const char* name) = 0;
-
-  // Returns a new timer task runner. This queue is intended for DOM Timers.
-  virtual scoped_refptr<TaskQueue> NewTimerTaskRunner(const char* name) = 0;
-
-  // Returns a task runner for tasks which should never get throttled.
-  virtual scoped_refptr<TaskQueue> NewUnthrottledTaskRunner(
-      const char* name) = 0;
-
-  // Returns a new RenderWidgetSchedulingState.  The signals from this will be
-  // used to make scheduling decisions.
-  virtual std::unique_ptr<RenderWidgetSchedulingState>
-  NewRenderWidgetSchedulingState() = 0;
-
-  // Called to notify about the start of an extended period where no frames
-  // need to be drawn. Must be called from the main thread.
-  virtual void BeginFrameNotExpectedSoon() = 0;
-
-  // Called to notify about the start of a new frame.  Must be called from the
-  // main thread.
-  virtual void WillBeginFrame(const cc::BeginFrameArgs& args) = 0;
-
-  // Called to notify that a previously begun frame was committed. Must be
-  // called from the main thread.
-  virtual void DidCommitFrameToCompositor() = 0;
-
-  // Keep RendererScheduler::InputEventStateToString in sync with this enum.
-  enum class InputEventState {
-    EVENT_CONSUMED_BY_COMPOSITOR,
-    EVENT_FORWARDED_TO_MAIN_THREAD,
-  };
-  static const char* InputEventStateToString(InputEventState input_event_state);
-
-  // Tells the scheduler that the system processed an input event. Called by the
-  // compositor (impl) thread.  Note it's expected that every call to
-  // DidHandleInputEventOnCompositorThread where |event_state| is
-  // EVENT_FORWARDED_TO_MAIN_THREAD will be followed by a corresponding call
-  // to DidHandleInputEventOnMainThread.
-  virtual void DidHandleInputEventOnCompositorThread(
-      const blink::WebInputEvent& web_input_event,
-      InputEventState event_state) = 0;
-
-  // Tells the scheduler that the system processed an input event. Must be
-  // called from the main thread.
-  virtual void DidHandleInputEventOnMainThread(
-      const blink::WebInputEvent& web_input_event) = 0;
-
-  // Tells the scheduler that the system is displaying an input animation (e.g.
-  // a fling). Called by the compositor (impl) thread.
-  virtual void DidAnimateForInputOnCompositorThread() = 0;
-
-  // Tells the scheduler that the renderer process has been backgrounded, i.e.,
-  // there are no critical, user facing activities (visual, audio, etc...)
-  // driven by this process. A stricter condition than |OnRendererHidden()|, the
-  // process is assumed to be foregrounded when the scheduler is constructed.
-  // Must be called on the main thread.
-  virtual void OnRendererBackgrounded() = 0;
-
-  // Tells the scheduler that the renderer process has been foregrounded.
-  // This is the assumed state when the scheduler is constructed.
-  // Must be called on the main thread.
-  virtual void OnRendererForegrounded() = 0;
-
-  // Tells the scheduler that the render process should be suspended. This can
-  // only be done when the renderer is backgrounded. The renderer will be
-  // automatically resumed when foregrounded.
-  virtual void SuspendRenderer() = 0;
-
-  // Tells the scheduler that a navigation task is pending. While any main-frame
-  // navigation tasks are pending, the scheduler will ensure that loading tasks
-  // are not blocked even if they are expensive. Must be called on the main
-  // thread.
-  virtual void AddPendingNavigation(
-      blink::WebScheduler::NavigatingFrameType type) = 0;
-
-  // Tells the scheduler that a navigation task is no longer pending.
-  // Must be called on the main thread.
-  virtual void RemovePendingNavigation(
-      blink::WebScheduler::NavigatingFrameType type) = 0;
-
-  // Tells the scheduler that a navigation has started.  The scheduler will
-  // prioritize loading tasks for a short duration afterwards.
-  // Must be called from the main thread.
-  virtual void OnNavigationStarted() = 0;
-
-  // Returns true if the scheduler has reason to believe that high priority work
-  // may soon arrive on the main thread, e.g., if gesture events were observed
-  // recently.
-  // Must be called from the main thread.
-  virtual bool IsHighPriorityWorkAnticipated() = 0;
-
-  // Suspends the timer queue and increments the timer queue suspension count.
-  // May only be called from the main thread.
-  virtual void SuspendTimerQueue() = 0;
-
-  // Decrements the timer queue suspension count and re-enables the timer queue
-  // if the suspension count is zero and the current schduler policy allows it.
-  virtual void ResumeTimerQueue() = 0;
-
-  // Sets whether to allow suspension of timers after the backgrounded signal is
-  // received via OnRendererBackgrounded. Defaults to disabled.
-  virtual void SetTimerQueueSuspensionWhenBackgroundedEnabled(bool enabled) = 0;
-
-  // Sets the default blame context to which top level work should be
-  // attributed in this renderer. |blame_context| must outlive this scheduler.
-  virtual void SetTopLevelBlameContext(
-      base::trace_event::BlameContext* blame_context) = 0;
-
-  // The renderer scheduler maintains an estimated RAIL mode[1]. This observer
-  // can be used to get notified when the mode changes. The observer will be
-  // called on the main thread and must outlive this class.
-  // [1]
-  // https://developers.google.com/web/tools/chrome-devtools/profile/evaluate-performance/rail
-  virtual void SetRAILModeObserver(RAILModeObserver* observer) = 0;
-
- protected:
-  RendererScheduler();
-  DISALLOW_COPY_AND_ASSIGN(RendererScheduler);
-};
-
-}  // namespace scheduler
-
-#endif  // COMPONENTS_SCHEDULER_RENDERER_RENDERER_SCHEDULER_H_