Pass accurate contentsScale to LayerImpl.

cc/scrollbar_layer.cc

 // Copyright 2012 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 "config.h"
 
 #include "cc/scrollbar_layer.h"
 
 #include "base/basictypes.h"
 #include "base/debug/trace_event.h"
@@ skipping 25 matching lines @@
     , m_textureFormat(GL_INVALID_ENUM)
 {
 }
 
 ScrollbarLayer::~ScrollbarLayer()
 {
 }
 
 void ScrollbarLayer::pushPropertiesTo(LayerImpl* layer)
 {
-    Layer::pushPropertiesTo(layer);
+    ContentsScalingLayer::pushPropertiesTo(layer);
 
     ScrollbarLayerImpl* scrollbarLayer = static_cast<ScrollbarLayerImpl*>(layer);
 
     if (!scrollbarLayer->scrollbarGeometry())
         scrollbarLayer->setScrollbarGeometry(ScrollbarGeometryFixedThumb::create(make_scoped_ptr(m_geometry->clone())));
 
     scrollbarLayer->setScrollbarData(m_scrollbar.get());
 
     if (m_backTrack && m_backTrack->texture()->haveBackingTexture())
         scrollbarLayer->setBackTrackResourceId(m_backTrack->texture()->resourceId());
@@ skipping 67 matching lines @@
     }
 
     WebKit::WebScrollbar* m_scrollbar;
     WebKit::WebScrollbarThemePainter m_painter;
     WebKit::WebScrollbarThemeGeometry* m_geometry;
     WebKit::WebScrollbar::ScrollbarPart m_trackPart;
 
     DISALLOW_COPY_AND_ASSIGN(ScrollbarBackgroundPainter);
 };
 
-bool ScrollbarLayer::needsContentsScale() const
-{
-    return true;
-}
-
-IntSize ScrollbarLayer::contentBounds() const
-{
-    return IntSize(lroundf(bounds().width() * contentsScale()), lroundf(bounds().height() * contentsScale()));
-}
-
 class ScrollbarThumbPainter : public LayerPainter {
 public:
     static scoped_ptr<ScrollbarThumbPainter> create(WebKit::WebScrollbar* scrollbar, WebKit::WebScrollbarThemePainter painter, WebKit::WebScrollbarThemeGeometry* geometry)
     {
         return make_scoped_ptr(new ScrollbarThumbPainter(scrollbar, painter, geometry));
     }
 
     virtual void paint(SkCanvas* skCanvas, const IntRect& contentRect, FloatRect& opaque) OVERRIDE
     {
         WebKit::WebCanvas* canvas = skCanvas;
@@ skipping 22 matching lines @@
 
 void ScrollbarLayer::setLayerTreeHost(LayerTreeHost* host)
 {
     if (!host || host != layerTreeHost()) {
         m_backTrackUpdater = NULL;
         m_backTrack.reset();
         m_thumbUpdater = NULL;
         m_thumb.reset();
     }
 
-    Layer::setLayerTreeHost(host);
+    ContentsScalingLayer::setLayerTreeHost(host);
 }
 
 void ScrollbarLayer::createUpdaterIfNeeded()
 {
     m_textureFormat = layerTreeHost()->rendererCapabilities().bestTextureFormat;
 
     if (!m_backTrackUpdater)
         m_backTrackUpdater = CachingBitmapContentLayerUpdater::Create(ScrollbarBackgroundPainter::create(m_scrollbar.get(), m_painter, m_geometry.get(), WebKit::WebScrollbar::BackTrackPart).PassAs<LayerPainter>());
     if (!m_backTrack)
         m_backTrack = m_backTrackUpdater->createResource(layerTreeHost()->contentsTextureManager());
@@ skipping 20 matching lines @@
             && texture->texture()->size() == rect.size()
             && m_updateRect.isEmpty())
         return;
 
     // We should always have enough memory for UI.
     DCHECK(texture->texture()->canAcquireBackingTexture());
     if (!texture->texture()->canAcquireBackingTexture())
         return;
 
     // Paint and upload the entire part.
-    float widthScale = static_cast<float>(contentBounds().width()) / bounds().width();
-    float heightScale = static_cast<float>(contentBounds().height()) / bounds().height();
     IntRect paintedOpaqueRect;
-    painter->prepareToUpdate(rect, rect.size(), widthScale, heightScale, paintedOpaqueRect, stats);
+    painter->prepareToUpdate(rect, rect.size(), contentsScaleX(), contentsScaleY(), paintedOpaqueRect, stats);
     if (!painter->pixelsDidChange() && texture->texture()->haveBackingTexture()) {
         TRACE_EVENT_INSTANT0("cc","ScrollbarLayer::updatePart no texture upload needed");
         return;
     }
 
     IntSize destOffset(0, 0);
     texture->update(queue, rect, destOffset, false, stats);
 }
 
 
@@ skipping 34 matching lines @@
         updatePart(m_foreTrackUpdater.get(), m_foreTrack.get(), contentRect, queue, stats);
 
     // Consider the thumb to be at the origin when painting.
     WebKit::WebRect thumbRect = m_geometry->thumbRect(m_scrollbar.get());
     IntRect originThumbRect = layerRectToContentRect(WebKit::WebRect(0, 0, thumbRect.width, thumbRect.height));
     if (!originThumbRect.isEmpty())
         updatePart(m_thumbUpdater.get(), m_thumb.get(), originThumbRect, queue, stats);
 }
 
 }