Zoom the web contents 2x such that they are blurry in High DPI

ui/compositor/layer.cc

 // Copyright (c) 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 "ui/compositor/layer.h"
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 560 matching lines @@
   if (!web_layer_is_accelerated_) {
     if (type_ != LAYER_SOLID_COLOR)
       web_layer_.to<WebKit::WebContentLayer>().setDrawsContent(should_draw);
     web_layer_.setBounds(ConvertSizeToPixel(this, bounds_.size()));
   } else {
     DCHECK(texture_);
     unsigned int texture_id = texture_->texture_id();
     WebKit::WebExternalTextureLayer texture_layer =
         web_layer_.to<WebKit::WebExternalTextureLayer>();
     texture_layer.setTextureId(should_draw ? texture_id : 0);
-    gfx::Rect bounds_in_pixel = ConvertRectToPixel(this, bounds());
     gfx::Size texture_size = texture_->size();
-    gfx::Size size(std::min(bounds_in_pixel.width(), texture_size.width()),
-                   std::min(bounds_in_pixel.height(), texture_size.height()));
+
+    // As WebKit does not support DIP, WebKit is told of coordinates in DIP
+    // as if they were pixel coordinates. The texture is scaled here via
+    // the setBounds call.
+    // TODO(pkotwicz): Fix this code to take in account textures with pixel
+    // sizes once WebKit understands DIP. http://crbug.com/127455

[piman, 2012/05/09 23:31:03]

Note: once you want to provide support for that, it should be handled similarly
to paintContents (i.e. base it on scale_canvas_, maybe rename that). I don't
want us to equate external texture == webkit, but instead have the client
(RenderWidgetHostViewAura) inform whether the texture is in pixels or in dip.

+    gfx::Size size(std::min(bounds().width(), texture_size.width()),
+                   std::min(bounds().height(), texture_size.height()));
     WebKit::WebFloatRect rect(
         0,
         0,
         static_cast<float>(size.width())/texture_size.width(),
         static_cast<float>(size.height())/texture_size.height());
     texture_layer.setUVRect(rect);
-    web_layer_.setBounds(size);
+
+    gfx::Size size_in_pixel = ConvertSizeToPixel(this, bounds().size());
+    web_layer_.setBounds(size_in_pixel);
   }
 }
 
 void Layer::RecomputeDebugBorderColor() {
   if (!show_debug_borders_)
     return;
   unsigned int color = 0xFF000000;
   color |= web_layer_is_accelerated_ ? 0x0000FF00 : 0x00FF0000;
   bool opaque = fills_bounds_opaquely_ && (GetCombinedOpacity() == 1.f);
   if (!opaque)
     color |= 0xFF;
   web_layer_.setDebugBorderColor(color);
 }
 
 }  // namespace ui