Move c/b/extension/api/* into extensions namespace

chrome/browser/extensions/api/downloads_internal/downloads_internal_api.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/extensions/api/downloads_internal/downloads_internal_api.h"
 
 #include "chrome/browser/extensions/api/downloads/downloads_api.h"
 #include "chrome/common/extensions/api/downloads.h"
 #include "chrome/common/extensions/api/downloads_internal.h"
 
+namespace extensions {
+
 DownloadsInternalDetermineFilenameFunction::
     DownloadsInternalDetermineFilenameFunction() {}
 
 DownloadsInternalDetermineFilenameFunction::
     ~DownloadsInternalDetermineFilenameFunction() {}
 
 typedef extensions::api::downloads_internal::DetermineFilename::Params
     DetermineFilenameParams;
 
 bool DownloadsInternalDetermineFilenameFunction::RunImpl() {
   scoped_ptr<DetermineFilenameParams> params(
       DetermineFilenameParams::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   base::FilePath::StringType filename;
   EXTENSION_FUNCTION_VALIDATE(args_->GetString(1, &filename));
   return ExtensionDownloadsEventRouter::DetermineFilename(
       profile(),
       include_incognito(),
       GetExtension()->id(),
       params->download_id,
       base::FilePath(filename),
       extensions::api::downloads::ParseFilenameConflictAction(
         params->conflict_action),
       &error_);
 }
+
+}  // namespace extensions