Video Player: Fix the private API error in Debug build

chrome/browser/chromeos/extensions/file_manager/private_api_drive.cc

 // Copyright 2013 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/chromeos/extensions/file_manager/private_api_drive.h"
 
 #include "base/command_line.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/drive/drive_integration_service.h"
 #include "chrome/browser/chromeos/extensions/file_manager/private_api_util.h"
@@ skipping 900 matching lines @@
       drive::util::GetFileSystemByProfile(GetProfile());
   if (!file_system) {
     // |file_system| is NULL if Drive is disabled or not mounted.
     SetError("Drive is disabled or not mounted.");
     SetResult(new base::StringValue(""));  // Intentionally returns a blank.
     return false;
   }
 
   const base::FilePath path = file_manager::util::GetLocalPathFromURL(
       render_view_host(), GetProfile(), GURL(params->url));
-  DCHECK(drive::util::IsUnderDriveMountPoint(path));
+  if (!drive::util::IsUnderDriveMountPoint(path)) {
+    SetError("The given file is not in Drive.");
+    SetResult(new base::StringValue(""));  // Intentionally returns a blank.
+    return false;
+  }
   base::FilePath file_path = drive::util::ExtractDrivePath(path);
 
   file_system->GetResourceEntry(
       file_path,
       base::Bind(&FileBrowserPrivateGetDownloadUrlFunction::OnGetResourceEntry,
                  this));
   return true;
 }
 
 void FileBrowserPrivateGetDownloadUrlFunction::OnGetResourceEntry(
@@ skipping 39 matching lines @@
     return;
   }
 
   const std::string url = download_url_ + "?access_token=" + access_token;
   SetResult(new base::StringValue(url));
 
   SendResponse(true);
 }
 
 }  // namespace extensions