Move download filename determintion into a separate class.

chrome/browser/download/download_prefs.cc

 // Copyright (c) 2012 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/download/download_prefs.h"
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 135 matching lines @@
 }
 
 bool DownloadPrefs::IsDownloadPathManaged() const {
   return download_path_.IsManaged();
 }
 
 bool DownloadPrefs::IsAutoOpenUsed() const {
   return !auto_open_.empty();
 }
 
-bool DownloadPrefs::IsAutoOpenEnabledForExtension(
-    const base::FilePath::StringType& extension) const {
+bool DownloadPrefs::IsAutoOpenEnabledBasedOnExtension(
+    const base::FilePath& path) const {
+  base::FilePath::StringType extension = path.Extension();
+  if (extension.empty())
+    return false;
+  DCHECK(extension[0] == base::FilePath::kExtensionSeparator);
+  extension.erase(0, 1);
   return auto_open_.find(extension) != auto_open_.end();
 }
 
 bool DownloadPrefs::EnableAutoOpenBasedOnExtension(
     const base::FilePath& file_name) {
   base::FilePath::StringType extension = file_name.Extension();
   if (extension.empty())
     return false;
   DCHECK(extension[0] == base::FilePath::kExtensionSeparator);
   extension.erase(0, 1);
@@ skipping 27 matching lines @@
     std::string this_extension = *it;
 #elif defined(OS_WIN)
     // TODO(phajdan.jr): Why we're using Sys conversion here, but not in ctor?
     std::string this_extension = base::SysWideToUTF8(*it);
 #endif
     extensions += this_extension + ":";
   }
   if (!extensions.empty())
     extensions.erase(extensions.size() - 1);
 
+  DCHECK(profile_);

[benjhayden, 2013/04/09 15:46:32]

I thought it was unnecessary to dcheck pointers that you're about to deref? The
stack trace will look the same.

[asanka, 2013/04/16 20:34:01]

Done.

+  DCHECK(profile_->GetPrefs());
   profile_->GetPrefs()->SetString(prefs::kDownloadExtensionsToOpen, extensions);
 }
 
 bool DownloadPrefs::AutoOpenCompareFunctor::operator()(
     const base::FilePath::StringType& a,
     const base::FilePath::StringType& b) const {
   return base::FilePath::CompareLessIgnoreCase(a, b);
 }