Removing base::ThreadRestrictions::ScopedAllowIO from icon_manager_linux.cc

chrome/browser/icon_manager_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_manager.h"
 
 #include "base/nix/mime_util_xdg.h"
 #include "base/threading/thread_restrictions.h"
 
-IconGroupID IconManager::GetGroupIDFromFilepath(
+IconGroupID IconManager::ReadGroupIDFromFilepath(
     const base::FilePath& filepath) {
-  // It turns out the call to base::nix::GetFileMimeType below does IO, but
-  // callers of GetGroupIDFromFilepath assume it does not do IO (the Windows
-  // and Mac implementations do not). We should fix this by either not doing IO
-  // in this method, or reworking callers to avoid calling it on the UI thread.
-  // See crbug.com/72740.
-  base::ThreadRestrictions::ScopedAllowIO allow_io;
-
   return base::nix::GetFileMimeType(filepath);
 }