Fix the dynamic browser action setIcon path to work with any size icon.

chrome/browser/ui/views/toolbar/toolbar_action_view.cc

Index: chrome/browser/ui/views/toolbar/toolbar_action_view.cc
diff --git a/chrome/browser/ui/views/toolbar/toolbar_action_view.cc b/chrome/browser/ui/views/toolbar/toolbar_action_view.cc
index 13198fb2a94c50b90ee6b74e2670a52b60461db8..237c76e208bb153125aea12b554556679a3d26f6 100644
--- a/chrome/browser/ui/views/toolbar/toolbar_action_view.cc
+++ b/chrome/browser/ui/views/toolbar/toolbar_action_view.cc
@@ -158,12 +158,8 @@ void ToolbarActionView::UpdateState() {
       view_controller_->GetIcon(web_contents,
                                 GetPreferredSize()).AsImageSkia());
 
-  if (!icon.isNull()) {
-    gfx::ImageSkia bg = *ResourceBundle::GetSharedInstance().GetImageSkiaNamed(

[Evan Stade, 2016/01/13 18:35:41]

this wasn't doing anything (except enlarging the image, which shouldn't be
necessary as the image gets centered) because the asset is just a fully
transparent png.

[Devlin, 2016/01/13 19:58:12]

Hmm... my guess is that maybe we *needed* to enlarge the icon at some point
(because we do utilize the area around the icon for, e.g., the badge).  But I
think all that code has migrated, so I think you're right that this is okay. 
We'll see if anything breaks.

[Evan Stade, 2016/01/14 01:59:19]

my personal guess is that the background asset used to be non-transparent (I
can't find any old screenshots to confirm this, but it's possible it just never
made it into a stable release)

-        IDR_BROWSER_ACTION);
-    SetImage(views::Button::STATE_NORMAL,
-             gfx::ImageSkiaOperations::CreateSuperimposedImage(bg, icon));
-  }
+  if (!icon.isNull())
+    SetImage(views::Button::STATE_NORMAL, icon);
 
   SetTooltipText(view_controller_->GetTooltip(web_contents));
   SetAccessibleName(view_controller_->GetAccessibleName(web_contents));