cc: Remove use of PassAs() and constructor-casting with scoped_ptr.

cc/layers/painted_scrollbar_layer.cc

 // Copyright 2013 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/layers/painted_scrollbar_layer.h"
 
 #include "base/auto_reset.h"
 #include "base/basictypes.h"
 #include "base/debug/trace_event.h"
 #include "cc/layers/painted_scrollbar_layer_impl.h"
 #include "cc/resources/ui_resource_bitmap.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/layer_tree_impl.h"
 #include "skia/ext/platform_canvas.h"
 #include "skia/ext/refptr.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkSize.h"
 #include "ui/gfx/skia_util.h"
 
 namespace cc {
 
 scoped_ptr<LayerImpl> PaintedScrollbarLayer::CreateLayerImpl(
     LayerTreeImpl* tree_impl) {
   return PaintedScrollbarLayerImpl::Create(
-      tree_impl, id(), scrollbar_->Orientation()).PassAs<LayerImpl>();
+      tree_impl, id(), scrollbar_->Orientation());
 }
 
 scoped_refptr<PaintedScrollbarLayer> PaintedScrollbarLayer::Create(
     scoped_ptr<Scrollbar> scrollbar,
     int scroll_layer_id) {
   return make_scoped_refptr(
       new PaintedScrollbarLayer(scrollbar.Pass(), scroll_layer_id));
 }
 
 PaintedScrollbarLayer::PaintedScrollbarLayer(scoped_ptr<Scrollbar> scrollbar,
@@ skipping 112 matching lines @@
       static_cast<PaintedScrollbarLayerImpl*>(layer);
 
   scrollbar_layer->SetScrollLayerAndClipLayerByIds(scroll_layer_id_,
                                                    clip_layer_id_);
 }
 
 void PaintedScrollbarLayer::SetLayerTreeHost(LayerTreeHost* host) {
   // When the LTH is set to null or has changed, then this layer should remove
   // all of its associated resources.
   if (!host || host != layer_tree_host()) {
-    track_resource_.reset();
-    thumb_resource_.reset();
+    track_resource_ = nullptr;
+    thumb_resource_ = nullptr;
   }
 
   ContentsScalingLayer::SetLayerTreeHost(host);
 }
 
 gfx::Rect PaintedScrollbarLayer::ScrollbarLayerRectToContentRect(
     const gfx::Rect& layer_rect) const {
   // Don't intersect with the bounds as in LayerRectToContentRect() because
   // layer_rect here might be in coordinates of the containing layer.
   gfx::Rect expanded_rect = gfx::ScaleToEnclosingRect(
@@ skipping 36 matching lines @@
   UpdateThumbAndTrackGeometry();
 
   gfx::Rect track_layer_rect = gfx::Rect(location_, bounds());
   gfx::Rect scaled_track_rect = ScrollbarLayerRectToContentRect(
       track_layer_rect);
 
   bool updated = false;
 
   if (track_rect_.IsEmpty() || scaled_track_rect.IsEmpty()) {
     if (track_resource_) {
-      track_resource_.reset();
-      if (thumb_resource_)
-        thumb_resource_.reset();
+      track_resource_ = nullptr;
+      thumb_resource_ = nullptr;
       SetNeedsPushProperties();
       updated = true;
     }
     return updated;
   }
 
   if (!has_thumb_ && thumb_resource_) {
-    thumb_resource_.reset();
+    thumb_resource_ = nullptr;
     SetNeedsPushProperties();
   }
 
   {
     base::AutoReset<bool> ignore_set_needs_commit(&ignore_set_needs_commit_,
                                                   true);
     ContentsScalingLayer::Update(queue, occlusion);
   }
 
   if (update_rect_.IsEmpty() && track_resource_)
@@ skipping 48 matching lines @@
 
   scrollbar_->PaintPart(&skcanvas, part, layer_rect);
   // Make sure that the pixels are no longer mutable to unavoid unnecessary
   // allocation and copying.
   skbitmap.setImmutable();
 
   return UIResourceBitmap(skbitmap);
 }
 
 }  // namespace cc