First round of dead file removal

experimental/visual_studio_plugin/src/NaClVsx.Package/DebugSupport/DWARF/ExtensionMethods.cs

-// Copyright (c) 2011 The Native Client Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#region
-
-using System.Collections.Generic;
-
-#endregion
-
-namespace Google.NaClVsx.DebugSupport.DWARF {
-  public static class ExtensionMethods {
-    public static T PeekOrDefault<T>(this Stack<T> s) where T : class {
-      if (s.Count == 0) {
-        return null;
-      }
-      return s.Peek();
-    }
-
-    public static T PeekOrDefault<T>(this Stack<T> s, T defaultValue) {
-      if (s.Count == 0) {
-        return defaultValue;
-      }
-      return s.Peek();
-    }
-
-    public static TV GetValueOrDefault<TK, TV>(this IDictionary<TK, TV> d,
-                                               TK key,
-                                               TV defaultValue) {
-      TV result;
-      if (!d.TryGetValue(key, out result)) {
-        result = defaultValue;
-      }
-      return result;
-    }
-  }
-}