Initial implementation of WorkletAnimation

third_party/WebKit/Source/core/animation/WorkletAnimationController.cpp

+// Copyright 2017 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 "core/animation/WorkletAnimationController.h"
+
+#include "core/animation/WorkletAnimationBase.h"
+
+namespace blink {
+
+WorkletAnimationController::WorkletAnimationController() = default;
+
+WorkletAnimationController::~WorkletAnimationController() = default;
+
+void WorkletAnimationController::AttachAnimation(
+    WorkletAnimationBase& animation) {
+  DCHECK(IsMainThread());
+  // TODO(smcgruer): Call NeedsCompositingUpdate on the relevant LocalFrameView.
+  DCHECK(!pending_animations_.Contains(&animation));
+  DCHECK(!compositor_animations_.Contains(&animation));
+  pending_animations_.insert(&animation);
+}
+
+void WorkletAnimationController::DetachAnimation(
+    WorkletAnimationBase& animation) {
+  DCHECK(IsMainThread());
+  DCHECK(pending_animations_.Contains(&animation) !=
+         compositor_animations_.Contains(&animation));
+  if (pending_animations_.Contains(&animation))
+    pending_animations_.erase(&animation);
+  else
+    compositor_animations_.erase(&animation);
+}
+
+void WorkletAnimationController::Update() {
+  DCHECK(IsMainThread());
+  HeapHashSet<Member<WorkletAnimationBase>> animations;
+  animations.swap(pending_animations_);
+  for (const auto& animation : animations) {
+    if (animation->StartOnCompositor()) {
+      compositor_animations_.insert(animation);
+    }
+    // TODO(smcgruer): On failure, warn user. Perhaps fire cancel event?
+  }
+}
+
+DEFINE_TRACE(WorkletAnimationController) {
+  visitor->Trace(pending_animations_);
+  visitor->Trace(compositor_animations_);
+}
+
+}  // namespace blink