Cleanup: Make ExtensionIconSet::Get return a const std::string& rather than a

extensions/browser/extension_icon_image.cc

 // Copyright 2014 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 "extensions/browser/extension_icon_image.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "content/public/browser/notification_service.h"
@@ skipping 29 matching lines @@
 
 namespace {
 
 const int kMatchBiggerTreshold = 32;
 
 extensions::ExtensionResource GetExtensionIconResource(
     const extensions::Extension* extension,
     const ExtensionIconSet& icons,
     int size,
     ExtensionIconSet::MatchType match_type) {
-  std::string path = icons.Get(size, match_type);
-  if (path.empty())
-    return extensions::ExtensionResource();
-
-  return extension->GetResource(path);
+  const std::string& path = icons.Get(size, match_type);
+  return path.empty() ? extensions::ExtensionResource()
+                      : extension->GetResource(path);
 }
 
 class BlankImageSource : public gfx::CanvasImageSource {
  public:
   explicit BlankImageSource(const gfx::Size& size_in_dip)
       : CanvasImageSource(size_in_dip, /*is_opaque =*/ false) {
   }
   virtual ~BlankImageSource() {}
 
  private:
@@ skipping 165 matching lines @@
                         const content::NotificationDetails& details) {
   DCHECK_EQ(type, extensions::NOTIFICATION_EXTENSION_REMOVED);
 
   const Extension* extension = content::Details<const Extension>(details).ptr();
 
   if (extension_ == extension)
     extension_ = NULL;
 }
 
 }  // namespace extensions