Use correct favicon scale factor on Android.

ui/gfx/android/device_display_info.h

+// 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.
+
+#ifndef UI_GFX_ANDROID_DEVICE_DISPLAY_INFO_H_
+#define UI_GFX_ANDROID_DEVICE_DISPLAY_INFO_H_
+
+#include <jni.h>
+#include <string>
+
+#include "base/android/scoped_java_ref.h"
+#include "base/basictypes.h"
+#include "ui/base/ui_export.h"
+
+namespace gfx {
+
+// Facilitates access to device information typically only
+// available using the Android SDK, including Display properties.
+class UI_EXPORT DeviceDisplayInfo {
+ public:
+  DeviceDisplayInfo();
+  ~DeviceDisplayInfo();
+
+  // Returns display height in physical pixels.
+  int GetDisplayHeight();
+
+  // Returns display width in physical pixels.
+  int GetDisplayWidth();
+
+  // Returns number of bits per pixel.
+  int GetBitsPerPixel();
+
+  // Returns number of bits per component.
+  int GetBitsPerComponent();
+
+  // Returns a scaling factor for Density Independent Pixel unit
+  // (1.0 is 160dpi, 0.75 is 120dpi, 2.0 is 320dpi).
+  double GetDIPScale();
+
+  // Returns display refresh rate in number of frames per second.
+  double GetRefreshRate();
+
+  // Registers methods with JNI and returns true if succeeded.
+  static bool RegisterDeviceDisplayInfo(JNIEnv* env);
+
+ private:
+  base::android::ScopedJavaGlobalRef<jobject> j_device_info_;
+
+  DISALLOW_COPY_AND_ASSIGN(DeviceDisplayInfo);
+};
+
+}  // namespace gfx
+
+#endif  // UI_GFX_ANDROID_DEVICE_DISPLAY_INFO_H_