Fix high-DPI on Windows to make use of DIP scaling in WebKit.

ui/base/resource/resource_bundle_win.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/base/resource/resource_bundle_win.h"
 
 #include "base/logging.h"
 #include "base/path_service.h"
 #include "base/utf_string_conversions.h"
 #include "ui/base/layout.h"
@@ skipping 23 matching lines @@
 }
 
 }  // namespace
 
 void ResourceBundle::LoadCommonResources() {
   // As a convenience, add the current resource module as a data packs.
   data_packs_.push_back(new ResourceDataDLL(GetCurrentResourceDLL()));
 
   bool use_hidpi = false;
 #if defined(ENABLE_HIDPI)
-  // If we're running in HiDPI mode at a scale larger than 150%, we switch
-  // to 2x resources for desktop layouts.
-  use_hidpi = ui::GetDPIScale() > 1.5;
+  // Have high-DPI resources for 140% and 180% scaling on Windows based on
+  // default scaling for Metro mode. If high-DPI mode is enabled, load resource
+  // pak closest to the desired scale factor.
+  use_hidpi = ui::GetDPIScale() > 1.2;

[pkotwicz, 2013/01/23 18:13:12]

For the purpose of this CL, you actually do not need the changes in
ResourceBundle

Nit: You can define scale depending on whether HIDPI is enabled.

Something like this:
#if defined(ENABLE_HIDPI)
float scale = ui::GetDPIScale();
#else
float scale = 1.0f;
#endif

[kevers, 2013/01/23 20:02:19]

Backing this change out for the time being.  Will keep feedback in mind when
reintroducing resource handling for High DPI.

 #endif
 
-  switch (ui::GetDisplayLayout()) {
-    case ui::LAYOUT_TOUCH:
-      AddDataPackFromPath(
-          GetResourcesPakFilePath("chrome_touch_100_percent.pak"),
-          SCALE_FACTOR_100P);
-      break;
-    default:
-      if (use_hidpi) {
-        AddDataPackFromPath(GetResourcesPakFilePath(
-                            "chrome_200_percent.pak"),
-                            SCALE_FACTOR_200P);
-        AddDataPackFromPath(GetResourcesPakFilePath(
-                            "webkit_resources_200_percent.pak"),
-                            SCALE_FACTOR_200P);
-      } else {
-        AddDataPackFromPath(
-            GetResourcesPakFilePath("chrome_100_percent.pak"),
-            SCALE_FACTOR_100P);
-      }
-      break;
+  if (use_hidpi) {
+    float scale = ui::GetDPIScale();
+    if (scale > 1.6f) {
+      AddDataPackFromPath(GetResourcesPakFilePath(
+          "chrome_touch_180_percent.pak"),
+          SCALE_FACTOR_180P);
+    } else {

[pkotwicz, 2013/01/23 18:13:12]

Nit: Put a comment that we will be using 1.4x resources for 1.25 and 1.5 scale
factors.
This is so that people like me who are unfamiliar with windows code are not
asking "Why are you not checking for (scale == 1.4f) ?"

[kevers, 2013/01/23 20:02:19]

Backing out change for now.

+      AddDataPackFromPath(GetResourcesPakFilePath(
+          "chrome_touch_140_percent.pak"),
+          SCALE_FACTOR_140P);
+    }
+
+    // Currently missing some scaled assets.  100% resources required as
+    // fallback.
+    AddDataPackFromPath(
+        GetResourcesPakFilePath("chrome_100_percent.pak"),
+        SCALE_FACTOR_100P);
+
+  } else if (ui::GetDisplayLayout() == ui::LAYOUT_TOUCH) {
+    AddDataPackFromPath(
+        GetResourcesPakFilePath("chrome_touch_100_percent.pak"),
+        SCALE_FACTOR_100P);
+  } else {
+    AddDataPackFromPath(
+        GetResourcesPakFilePath("chrome_100_percent.pak"),
+        SCALE_FACTOR_100P);
   }
 }
 
 gfx::Image& ResourceBundle::GetNativeImageNamed(int resource_id, ImageRTL rtl) {
   // Flipped image is not used on Windows.
   DCHECK_EQ(rtl, RTL_DISABLED);
 
   // Windows only uses SkBitmap for gfx::Image, so this is the same as
   // GetImageNamed.
   return GetImageNamed(resource_id);
 }
 
 void SetResourcesDataDLL(HINSTANCE handle) {
   resources_data_dll = handle;
 }
 
 HICON LoadThemeIconFromResourcesDataDLL(int icon_id) {
   return ::LoadIcon(GetCurrentResourceDLL(), MAKEINTRESOURCE(icon_id));
 }
 
 }  // namespace ui;