enable download protection on CrOS

content/browser/download/download_item_impl.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.
 
 // File method ordering: Methods in this file are in the same order as
 // in download_item_impl.h, with the following exception: The public
 // interface Start is placed in chronological order with the other
 // (private) routines that together define a DownloadItem's state
 // transitions as the download progresses.  See "Download progression
 // cascade" later in this file.
@@ skipping 648 matching lines @@
     return;
   }
   BrowserThread::PostTaskAndReplyWithResult(
       BrowserThread::FILE, FROM_HERE,
       base::Bind(&DeleteDownloadedFile, current_path_),
       base::Bind(&DeleteDownloadedFileDone,
                  weak_ptr_factory_.GetWeakPtr(), callback));
 }
 
 bool DownloadItemImpl::IsDangerous() const {
-#if defined(OS_WIN) || defined(OS_MACOSX)
+#if defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_CHROMEOS)
   // TODO(noelutz): At this point only the windows views and OSX UI supports
   // warnings based on dangerous content.
   return (danger_type_ == DOWNLOAD_DANGER_TYPE_DANGEROUS_FILE ||
           danger_type_ == DOWNLOAD_DANGER_TYPE_DANGEROUS_URL ||
           danger_type_ == DOWNLOAD_DANGER_TYPE_DANGEROUS_CONTENT ||
           danger_type_ == DOWNLOAD_DANGER_TYPE_UNCOMMON_CONTENT ||
           danger_type_ == DOWNLOAD_DANGER_TYPE_DANGEROUS_HOST ||
           danger_type_ == DOWNLOAD_DANGER_TYPE_POTENTIALLY_UNWANTED);
 #else
   return (danger_type_ == DOWNLOAD_DANGER_TYPE_DANGEROUS_FILE ||
@@ skipping 1125 matching lines @@
     case RESUME_MODE_USER_CONTINUE:
       return "USER_CONTINUE";
     case RESUME_MODE_USER_RESTART:
       return "USER_RESTART";
   }
   NOTREACHED() << "Unknown resume mode " << mode;
   return "unknown";
 }
 
 }  // namespace content