WIP - compositor worker mega patch.

cc/animation/layer_tree_mutation.h

Index: cc/animation/layer_tree_mutation.h
diff --git a/cc/animation/layer_tree_mutation.h b/cc/animation/layer_tree_mutation.h
new file mode 100644
index 0000000000000000000000000000000000000000..9f0984ba6dcc9d3a558e8a79d9a4583bdccd3158
--- /dev/null
+++ b/cc/animation/layer_tree_mutation.h
@@ -0,0 +1,74 @@
+// Copyright 2015 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 CC_ANIMATION_LAYER_TREE_MUTATION_H_
+#define CC_ANIMATION_LAYER_TREE_MUTATION_H_
+
+#include "base/containers/hash_tables.h"
+#include "third_party/skia/include/utils/SkMatrix44.h"
+
+namespace cc {
+
+// TODO(vollick): Once the repos merge, we can get rid of this class (which
+// duplicates WebLayerTreeMutation).
+struct LayerTreeMutation {
+ public:
+  enum MutationFlags {
+    MUTATION_NONE = 0,
+    MUTATION_OPACITY = 1 << 0,
+    MUTATION_SCROLL_LEFT = 1 << 1,
+    MUTATION_SCROLL_TOP = 1 << 2,
+    MUTATION_TRANSFORM = 1 << 3,
+    MUTATION_TRANSFORM_RELATED =
+        MUTATION_TRANSFORM | MUTATION_SCROLL_TOP | MUTATION_SCROLL_LEFT
+  };
+
+  void SetOpacity(float opacity) {
+    mutated_flags_ |= MUTATION_OPACITY;
+    opacity_ = opacity;
+  }
+  void SetScrollLeft(float scroll_left) {
+    mutated_flags_ |= MUTATION_SCROLL_LEFT;
+    scroll_left_ = scroll_left;
+  }
+  void SetScrollTop(float scroll_top) {
+    mutated_flags_ |= MUTATION_SCROLL_TOP;
+    scroll_top_ = scroll_top;
+  }
+  void SetTransform(const SkMatrix44& transform) {
+    mutated_flags_ |= MUTATION_TRANSFORM;
+    transform_ = transform;
+  }
+
+  bool is_opacity_mutated() const {
+    return !!(mutated_flags_ & MUTATION_OPACITY);
+  }
+  bool is_scroll_left_mutated() const {
+    return !!(mutated_flags_ & MUTATION_SCROLL_LEFT);
+  }
+  bool is_scroll_top_mutated() const {
+    return !!(mutated_flags_ & MUTATION_SCROLL_TOP);
+  }
+  bool is_transform_mutated() const {
+    return !!(mutated_flags_ & MUTATION_TRANSFORM);
+  }
+
+  float opacity() const { return opacity_; }
+  float scroll_left() const { return scroll_left_; }
+  float scroll_top() const { return scroll_top_; }
+  SkMatrix44 transform() const { return transform_; }
+
+ private:
+  uint32_t mutated_flags_ = 0;
+  float opacity_ = 0;
+  float scroll_left_ = 0;
+  float scroll_top_ = 0;
+  SkMatrix44 transform_;
+};
+
+typedef base::hash_map<uint64_t, LayerTreeMutation> LayerTreeMutationMap;
+
+}  // namespace cc
+
+#endif  // CC_ANIMATION_LAYER_TREE_MUTATION_H_