Mac: Fix icons in download dom UI

chrome/browser/icon_loader_linux.cc

 // Copyright (c) 2011 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/icon_loader.h"
 
 #include <gdk-pixbuf/gdk-pixbuf.h>
 #include <gio/gio.h>
 #include <gtk/gtk.h>
 
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/mime_util.h"
 #include "base/threading/thread.h"
 #include "base/string_util.h"
 
 static int SizeToInt(IconLoader::IconSize size) {
-  int pixels = 48;
-  if (size == IconLoader::NORMAL)
-    pixels = 32;
-  else if (size == IconLoader::SMALL)
-    pixels = 16;
-
+  int pixels = 0;
+  switch (size) {
+    case IconLoader::SMALL:
+      pixels = 16;
+      break;
+    case IconLoader::NORMAL:
+      pixels = 32;
+      break;
+    case IconLoader::LARGE:
+      pixels = 48;
+      break;
+    default:
+      NOTREACHED();
+  }
   return pixels;
 }
 
 void IconLoader::ReadIcon() {
   filename_ = mime_util::GetMimeIcon(group_, SizeToInt(icon_size_));
   file_util::ReadFileToString(filename_, &icon_data_);
   target_message_loop_->PostTask(FROM_HERE,
       NewRunnableMethod(this, &IconLoader::ParseIcon));
 }
 
@@ skipping 19 matching lines @@
     image_.reset(new gfx::Image(pixbuf));
   } else {
     LOG(WARNING) << "Unsupported file type or load error: " <<
                     filename_.value();
   }
 
   g_object_unref(loader);
 
   NotifyDelegate();
 }