Reland of Move scaling of ui resources for scrollbars to the time of upload

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 <algorithm>
 
 #include "base/auto_reset.h"
 #include "cc/base/math_util.h"
@@ skipping 60 matching lines @@
 }
 
 bool PaintedScrollbarLayer::AlwaysUseActiveTreeOpacity() const {
   return true;
 }
 
 ScrollbarOrientation PaintedScrollbarLayer::orientation() const {
   return scrollbar_->Orientation();
 }
 
-int PaintedScrollbarLayer::MaxTextureSize() {
-  DCHECK(layer_tree_host());
-  return layer_tree_host()->GetRendererCapabilities().max_texture_size;
-}
-
-float PaintedScrollbarLayer::ClampScaleToMaxTextureSize(float scale) {
-  // If the scaled bounds() is bigger than the max texture size of the
-  // device, we need to clamp it by rescaling, since this is used
-  // below to set the texture size.
-  gfx::Size scaled_bounds = gfx::ScaleToCeiledSize(bounds(), scale);
-  if (scaled_bounds.width() > MaxTextureSize() ||
-      scaled_bounds.height() > MaxTextureSize()) {
-    if (bounds().width() > bounds().height())
-      return (MaxTextureSize() - 1) / static_cast<float>(bounds().width());
-    else
-      return (MaxTextureSize() - 1) / static_cast<float>(bounds().height());
-  }
-  return scale;
-}
-
 void PaintedScrollbarLayer::PushPropertiesTo(LayerImpl* layer) {
   Layer::PushPropertiesTo(layer);
 
   PaintedScrollbarLayerImpl* scrollbar_layer =
       static_cast<PaintedScrollbarLayerImpl*>(layer);
 
   scrollbar_layer->SetScrollLayerId(scroll_layer_id_);
   scrollbar_layer->set_internal_contents_scale_and_bounds(
       internal_contents_scale_, internal_content_bounds_);
 
@@ skipping 84 matching lines @@
           .layer_transforms_should_scale_layer_contents) {
     gfx::Transform transform;
     transform = draw_property_utils::ScreenSpaceTransform(
         this, GetLayerTree()->property_trees()->transform_tree);
 
     gfx::Vector2dF transform_scales =
         MathUtil::ComputeTransform2dScaleComponents(transform, scale);
     scale = std::max(transform_scales.x(), transform_scales.y());
   }
   bool changed = false;
-  changed |= UpdateProperty(ClampScaleToMaxTextureSize(scale),
-                            &internal_contents_scale_);
+  changed |= UpdateProperty(scale, &internal_contents_scale_);
   changed |=
       UpdateProperty(gfx::ScaleToCeiledSize(bounds(), internal_contents_scale_),
                      &internal_content_bounds_);
   if (changed) {
     // If the content scale or bounds change, repaint.
     SetNeedsDisplay();
   }
 }
 
 bool PaintedScrollbarLayer::Update() {
@@ skipping 87 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