Ensure that the extension icons show up in the omnibox at fractional scales.

extensions/browser/extension_icon_image.cc

Index: extensions/browser/extension_icon_image.cc
diff --git a/extensions/browser/extension_icon_image.cc b/extensions/browser/extension_icon_image.cc
index 5ebc40017920f6190631bb21baf4fb5030308d28..31ddd615c18a9e06fdb5739fc0e915a3e4ac9dd3 100644
--- a/extensions/browser/extension_icon_image.cc
+++ b/extensions/browser/extension_icon_image.cc
@@ -11,6 +11,7 @@
 #include "extensions/browser/image_loader.h"
 #include "extensions/browser/notification_types.h"
 #include "extensions/common/extension.h"
+#include "ui/base/layout.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/geometry/size_conversions.h"
@@ -223,7 +224,21 @@ void IconImage::OnImageLoaded(float scale, const gfx::Image& image_in) {
   DCHECK(!rep.is_null());
   DCHECK_EQ(scale, rep.scale());
 
-  // Remove old representation if there is one.
+  // Remove fractional scale image representations as they may have become
+  // stale here. These images are generated by ImageSkia on request from
+  // supported scales like 1x, 2x, etc.
+  // TODO(oshima)
+  // A better approach might be to set the |image_| member using the ImageSkia
+  // copy from the image passed in and set the |image_skia_| member using
+  // image_.ToImageSkia(). However that does not work correctly as the
+  // ImageSkia from the image does not contain a source which breaks requests
+  // for scaled images.
+  std::vector<gfx::ImageSkiaRep> reps = image_skia_.image_reps();
+  for (const auto rep : reps) {

[brucedawson, 2015/03/26 18:44:37]

The declaration of 'rep' should, I believe, be "const auto& rep" in order to
avoid a gratuitous copy of the ImageSkiaRep object. The copy isn't super
expensive, but still probably worth avoiding.

Also, 'rep' shadows the same-named variable in the outer scope. This isn't a bug
but it can lead to confusion about which variable was intended. Consider
renaming the inner 'rep'? I noticed this because of a new variable shadowing
warning from /analyze.

[ananta, 2015/03/26 18:48:20]

Will address these in a followup

Thanks
Ananta

+    if (!ui::IsSupportedScale(rep.scale()))
+      image_skia_.RemoveRepresentation(rep.scale());
+  }
+
   image_skia_.RemoveRepresentation(scale);
   image_skia_.AddRepresentation(rep);