Remove unused libpeerconnection code.

third_party/libjingle/overrides/allocator_shim/allocator_stub.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 "third_party/libjingle/overrides/allocator_shim/allocator_stub.h"
-
-#if defined(OS_MACOSX) || defined(OS_ANDROID)
-#error "The allocator stub isn't supported (or needed) on mac or android."
-#endif
-
-void* Allocate(std::size_t n) {
-  return operator new(n);
-}
-
-void Dellocate(void* p) {
-  return operator delete(p);
-}