Support high dpi in menu scroll arrow, submenu arrow and drag_utils.

ui/base/dragdrop/drag_utils.cc

Index: ui/base/dragdrop/drag_utils.cc
diff --git a/ui/base/dragdrop/drag_utils.cc b/ui/base/dragdrop/drag_utils.cc
index 41f422e8a3c9951b9352a19c860f3cd4c282db54..f411809995dc3253275b4d7941a5e6f53c7dd654 100644
--- a/ui/base/dragdrop/drag_utils.cc
+++ b/ui/base/dragdrop/drag_utils.cc
@@ -12,54 +12,87 @@
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/font.h"
+#include "ui/gfx/image/canvas_image_source.h"
 #include "ui/gfx/point.h"
 #include "ui/gfx/size.h"
 
 namespace drag_utils {
-
+namespace {
 // Maximum width of the link drag image in pixels.
-static const int kLinkDragImageVPadding = 3;
+const int kLinkDragImageVPadding = 3;
 
 // File dragging pixel measurements
-static const int kFileDragImageMaxWidth = 200;
-static const SkColor kFileDragImageTextColor = SK_ColorBLACK;
+const int kFileDragImageMaxWidth = 200;
+const SkColor kFileDragImageTextColor = SK_ColorBLACK;
 
-void CreateDragImageForFile(const FilePath& file_name,
-                            const gfx::ImageSkia* icon,
-                            ui::OSExchangeData* data_object) {
-  DCHECK(icon);
-  DCHECK(data_object);
-
-  // Set up our text portion
+gfx::Size GetImageSize(const gfx::ImageSkia& icon) {
   ResourceBundle& rb = ResourceBundle::GetSharedInstance();
   gfx::Font font = rb.GetFont(ResourceBundle::BaseFont);
 
   const int width = kFileDragImageMaxWidth;
   // Add +2 here to allow room for the halo.
-  const int height = font.GetHeight() + icon->height() +
-                     kLinkDragImageVPadding + 2;
-  gfx::Canvas canvas(gfx::Size(width, height), false /* translucent */);
+  const int height = font.GetHeight() + icon.height() +
+      kLinkDragImageVPadding + 2;
+  return gfx::Size(width, height);
+}
 
-  // Paint the icon.
-  canvas.DrawImageInt(*icon, (width - icon->width()) / 2, 0);
+class DragImageSource : public gfx::CanvasImageSource {
+ public:
+  DragImageSource(const gfx::ImageSkia& icon, const string16& name)
+      : CanvasImageSource(GetImageSize(icon), false /* translucent */),
+        icon_(icon),
+        name_(name) {
+  }
+  virtual ~DragImageSource() {}
 
-  string16 name = file_name.BaseName().LossyDisplayName();
-  const int flags = gfx::Canvas::TEXT_ALIGN_CENTER;
+  // gfx::CanvasImageSource overrides:
+  virtual void Draw(gfx::Canvas* canvas) OVERRIDE {
+    // Set up our text portion
+    ResourceBundle& rb = ResourceBundle::GetSharedInstance();
+    gfx::Font font = rb.GetFont(ResourceBundle::BaseFont);
+
+    int width = size().width();
+    // Paint the icon.
+    canvas->DrawImageInt(icon_, (width - icon_.width()) / 2, 0);
+
+    const int flags = gfx::Canvas::TEXT_ALIGN_CENTER;
 #if defined(OS_WIN)
-  // Paint the file name. We inset it one pixel to allow room for the halo.
-  canvas.DrawStringWithHalo(name, font, kFileDragImageTextColor, SK_ColorWHITE,
-                            1, icon->height() + kLinkDragImageVPadding + 1,
-                            width - 2, font.GetHeight(), flags);
+    // Paint the file name. We inset it one pixel to allow room for the halo.
+    canvas->DrawStringWithHalo(name_, font,
+                               kFileDragImageTextColor, SK_ColorWHITE,
+                               1, icon_.height() + kLinkDragImageVPadding + 1,
+                               width - 2, font.GetHeight(), flags);
 #else
-  // NO_SUBPIXEL_RENDERING is required when drawing to a non-opaque canvas.
-  canvas.DrawStringInt(name, font, kFileDragImageTextColor,
-                       0, icon->height() + kLinkDragImageVPadding,
-                       width, font.GetHeight(),
-                       flags | gfx::Canvas::NO_SUBPIXEL_RENDERING);
+    // NO_SUBPIXEL_RENDERING is required when drawing to a non-opaque canvas.
+    canvas->DrawStringInt(name_, font,
+                          kFileDragImageTextColor,
+                          0, icon_.height() + kLinkDragImageVPadding,
+                          width, font.GetHeight(),
+                          flags | gfx::Canvas::NO_SUBPIXEL_RENDERING);
 #endif
+  }
+
+ private:
+  const gfx::ImageSkia icon_;
+  const string16 name_;
+
+  DISALLOW_COPY_AND_ASSIGN(DragImageSource);
+};
+
+}  // namespace
+
+void CreateDragImageForFile(const FilePath& file_name,
+                            const gfx::ImageSkia* icon,
+                            ui::OSExchangeData* data_object) {
+  DCHECK(icon);
+  DCHECK(data_object);
+
+  string16 name = file_name.BaseName().LossyDisplayName();
+  DragImageSource* source = new DragImageSource(*icon, name);
+  gfx::Size size = source->size();
 
-  SetDragImageOnDataObject(canvas, gfx::Size(width, height),
-                           gfx::Point(width / 2, kLinkDragImageVPadding),
+  SetDragImageOnDataObject(gfx::ImageSkia(source, size), size,
+                           gfx::Point(size.width() / 2, kLinkDragImageVPadding),
                            data_object);
 }