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

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

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/views/toolbar/toolbar_action_view.h"
 
 #include <string>
 
 #include "base/auto_reset.h"
 #include "chrome/browser/chrome_notification_types.h"
@@ skipping 140 matching lines @@
   } else if (state() == views::CustomButton::STATE_DISABLED) {
     SetState(views::CustomButton::STATE_NORMAL);
   }
 
   wants_to_run_ = view_controller_->WantsToRun(web_contents);
 
   gfx::ImageSkia icon(
       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));
 
   Layout();  // We need to layout since we may have added an icon as a result.
   SchedulePaint();
 }
 
 void ToolbarActionView::OnMenuButtonClicked(views::View* sender,
                                             const gfx::Point& point) {
@@ skipping 184 matching lines @@
     if (menu_controller->in_nested_run()) {
       // There is another menu showing. Close the outermost menu (since we are
       // shown in the same menu, we don't want to close the whole thing).
       menu_controller->Cancel(views::MenuController::EXIT_OUTERMOST);
       return true;
     }
   }
 
   return false;
 }