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

ui/gfx/display.cc

Index: ui/gfx/display.cc
diff --git a/ui/gfx/display.cc b/ui/gfx/display.cc
index 5b375891ad0fa271aae4cc990c0f116a724eabc7..f7227a40e86423f794c50317efb8cdbfe9bc2d92 100644
--- a/ui/gfx/display.cc
+++ b/ui/gfx/display.cc
@@ -9,25 +9,33 @@
 #include "base/string_number_conversions.h"
 #include "base/stringprintf.h"
 #include "ui/base/ui_base_switches.h"
+#include "ui/base/win/dpi.h"
 #include "ui/gfx/insets.h"
 #include "ui/gfx/size_conversions.h"
 
 namespace gfx {
 namespace {
 
-bool HasForceDeviceScaleFactor() {
+bool HasForceDeviceScaleFactorImpl() {
   return CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kForceDeviceScaleFactor);
 }
 
 float GetForcedDeviceScaleFactorImpl() {
   double scale_in_double = 1.0;
-  if (HasForceDeviceScaleFactor()) {
+  if (HasForceDeviceScaleFactorImpl()) {
     std::string value = CommandLine::ForCurrentProcess()->
         GetSwitchValueASCII(switches::kForceDeviceScaleFactor);
     if (!base::StringToDouble(value, &scale_in_double))
       LOG(ERROR) << "Failed to parse the deafult device scale factor:" << value;
   }
+#if defined(OS_WIN)
+  else {
+    static double os_scale = ui::GetDPIScale();
+    scale_in_double = os_scale;
+  }
+#endif
+
   return static_cast<float>(scale_in_double);
 }
 
@@ -41,6 +49,10 @@ float Display::GetForcedDeviceScaleFactor() {
       GetForcedDeviceScaleFactorImpl();
   return kForcedDeviceScaleFactor;
 }
+//static
+bool Display::HasForceDeviceScaleFactor() {
+  return HasForceDeviceScaleFactorImpl();
+}
 
 // static
 int64 Display::GetID(uint16 manufacturer_id, uint32 serial_number) {
@@ -64,7 +76,7 @@ Display::Display(int64 id, const gfx::Rect& bounds)
       bounds_(bounds),
       work_area_(bounds),
       device_scale_factor_(GetForcedDeviceScaleFactor()) {
-#if defined(USE_AURA)
+#if defined(USE_AURA) || defined(OS_WIN)
   SetScaleAndBounds(device_scale_factor_, bounds);
 #endif
 }
@@ -92,7 +104,7 @@ void Display::SetScaleAndBounds(
     device_scale_factor_ = device_scale_factor;
   }
   device_scale_factor_ = std::max(1.0f, device_scale_factor_);
-#if defined(USE_AURA)
+#if defined(USE_AURA) || defined(OS_WIN)
   bounds_in_pixel_ = bounds_in_pixel;
 #endif
   bounds_ = gfx::Rect(gfx::ToFlooredSize(
@@ -103,7 +115,7 @@ void Display::SetScaleAndBounds(
 void Display::SetSize(const gfx::Size& size_in_pixel) {
   SetScaleAndBounds(
       device_scale_factor_,
-#if defined(USE_AURA)
+#if defined(USE_AURA) || defined(OS_WIN)
       gfx::Rect(bounds_in_pixel_.origin(), size_in_pixel));
 #else
       gfx::Rect(bounds_.origin(), size_in_pixel));