Refactor GestureNavigation to eliminate code redundancy

content/browser/web_contents/aura/overscroll_layer_wrapper.cc

+// 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.
+
+#include "content/browser/web_contents/aura/overscroll_layer_wrapper.h"
+
+#include "ui/aura/window.h"
+#include "ui/compositor/layer.h"
+
+namespace content {
+
+OverscrollLayerWrapper::OverscrollLayerWrapper(scoped_ptr<aura::Window> window)
+    : layer_(nullptr),
+      window_(window.Pass()) {
+}
+
+OverscrollLayerWrapper::OverscrollLayerWrapper(scoped_ptr<ui::Layer> layer)
+    : layer_(layer.Pass()),
+      window_(nullptr) {
+}
+
+OverscrollLayerWrapper::~OverscrollLayerWrapper() {
+}
+
+scoped_ptr<ui::Layer> OverscrollLayerWrapper::AcquireLayer() {
+  return layer_.Pass();
+}
+
+scoped_ptr<aura::Window> OverscrollLayerWrapper::AcquireWindow() {
+  return window_.Pass();
+}
+
+gfx::Rect OverscrollLayerWrapper::GetBounds() {
+  if (layer_)
+    return layer_->bounds();
+  DCHECK(window_);
+  return window_->bounds();
+}
+
+}  // namespace content