Keep only base/extractor.[cc|h].

base/has_exception_namespace_fix.h

Index: base/has_exception_namespace_fix.h
diff --git a/base/has_exception_namespace_fix.h b/base/has_exception_namespace_fix.h
deleted file mode 100644
index e4f636706fe3c5bf132ee0edc2777dc26552e69d..0000000000000000000000000000000000000000
--- a/base/has_exception_namespace_fix.h
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2009 Google Inc.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-// ========================================================================
-
-#if !_HAS_EXCEPTIONS
-// Fixes a problem with using the standard library with exceptions turned off.
-// See discussion at http://tiny.cc/byLhe
-#include <exception>
-using std::exception;
-#endif