Enable hidpi on Linux, refactor a bit on Windows to share

ui/gfx/canvas_paint_win.cc

Index: ui/gfx/canvas_paint_win.cc
diff --git a/ui/gfx/canvas_paint_win.cc b/ui/gfx/canvas_paint_win.cc
index 7d20fbcd1c88355358cfc574876625e9173b1df5..81c44986ae5be1666aceb7b2d07c2ba6a526322f 100644
--- a/ui/gfx/canvas_paint_win.cc
+++ b/ui/gfx/canvas_paint_win.cc
@@ -55,18 +55,16 @@ void CanvasSkiaPaint::Init(bool opaque) {
   const int width = ps_.rcPaint.right - ps_.rcPaint.left;
   const int height = ps_.rcPaint.bottom - ps_.rcPaint.top;
 
-  RecreateBackingCanvas(gfx::Size(width, height),
-      gfx::win::GetDeviceScaleFactor(),
-      opaque);
+  RecreateBackingCanvas(
+      gfx::Size(width, height), gfx::GetDeviceScaleFactor(), opaque);
   skia::PlatformCanvas* canvas = platform_canvas();
 
   canvas->clear(SkColorSetARGB(0, 0, 0, 0));
 
   // This will bring the canvas into the screen coordinate system for the
   // dirty rect
-  canvas->translate(
-      -ps_.rcPaint.left / gfx::win::GetDeviceScaleFactor(),
-      -ps_.rcPaint.top / gfx::win::GetDeviceScaleFactor());
+  canvas->translate(-ps_.rcPaint.left / gfx::GetDeviceScaleFactor(),
+                    -ps_.rcPaint.top / gfx::GetDeviceScaleFactor());
 }
 
 }  // namespace gfx