This CL adds a new object: ImageSkiaRep

The object represents an SkBitmap and the scale factor that it is painted at.
The CL also changes the ImageSkia API to use ui::ScaleFactor instead of floats.

In Chromium, having this object is useful because it makes extracting an SkBitmap from an ImageSkia object and packing it back into an ImageSkia object easier.
In particular, this makes:
float scale_factor;
SkBitmap bitmap = input_image->GetBitmapForScale(1.0f, &scale_factor);
// do some work with the bitmap
gfx::ImageSkia output_image(bitmap, scale_factor);

into

gfx::ImageSkiaRep image_rep = input_image->GetRepresentation(ui::SCALE_FACTOR_100P);
// do some work with the image_rep
gfx::ImageSkia output_image(image_rep);

R=sky
TBR=sadrul for chrome/browser/chromeos/status

Review URL: https://chromiumcodereview.appspot.com/10448070

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@143940 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 6 insertions, 2 deletions

diff --git a/ui/gfx/canvas.cc b/ui/gfx/canvas.cc
index 5dbb00e..a7bc247 100644
--- a/ui/gfx/canvas.cc
+++ b/ui/gfx/canvas.cc
@@ -474,8 +474,12 @@ const SkBitmap& Canvas::GetBitmapToPaint(const gfx::ImageSkia& image,
   float scale_y = SkScalarToFloat(SkScalarAbs(m.getScaleY())) *
       user_additional_scale_y;
 
-  const SkBitmap& bitmap = image.GetBitmapForScale(scale_x, scale_y,
-                                                   bitmap_scale_factor);
+  ui::ScaleFactor request_scale_factor =
+      ui::GetScaleFactorFromScale((scale_x + scale_y) / 2);
+  const gfx::ImageSkiaRep& image_rep =
+      image.GetRepresentation(request_scale_factor);
+  const SkBitmap& bitmap = image_rep.sk_bitmap();
+  *bitmap_scale_factor = image_rep.GetScale();
   if (!bitmap.isNull() &&
       (scale_x < *bitmap_scale_factor || scale_y < *bitmap_scale_factor))
     const_cast<SkBitmap&>(bitmap).buildMipMap();