cc: Simplify Task and its derived classes.

cc/raster/task_graph_runner.cc

-// 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.
-
-#include "cc/raster/task_graph_runner.h"
-
-#include <algorithm>
-#include <utility>
-
-#include "base/atomic_sequence_num.h"
-#include "base/threading/thread_restrictions.h"
-#include "base/trace_event/trace_event.h"
-
-namespace cc {
-
-Task::Task() : will_run_(false), did_run_(false) {}
-
-Task::~Task() {
-  DCHECK(!will_run_);
-}
-
-void Task::WillRun() {
-  DCHECK(!will_run_);
-  DCHECK(!did_run_);
-  will_run_ = true;
-}
-
-void Task::DidRun() {
-  DCHECK(will_run_);
-  will_run_ = false;
-  did_run_ = true;
-}
-
-bool Task::HasFinishedRunning() const {
-  return did_run_;
-}
-
-TaskGraph::TaskGraph() {}
-
-TaskGraph::TaskGraph(const TaskGraph& other) = default;
-
-TaskGraph::~TaskGraph() {}
-
-void TaskGraph::Swap(TaskGraph* other) {
-  nodes.swap(other->nodes);
-  edges.swap(other->edges);
-}
-
-void TaskGraph::Reset() {
-  nodes.clear();
-  edges.clear();
-}
-
-}  // namespace cc