Remove renderer notifications of memory pressure.

content/public/browser/memory_pressure_controller.cc

-// Copyright 2016 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 "content/public/browser/memory_pressure_controller.h"
-
-#include "content/browser/memory/memory_pressure_controller_impl.h"
-
-namespace content {
-
-// static
-void MemoryPressureController::SendPressureNotification(
-    const BrowserChildProcessHost* child_process_host,
-    base::MemoryPressureListener::MemoryPressureLevel level) {
-  MemoryPressureControllerImpl::GetInstance()->SendPressureNotification(
-      child_process_host, level);
-}
-
-// static
-void MemoryPressureController::SendPressureNotification(
-    const RenderProcessHost* render_process_host,
-    base::MemoryPressureListener::MemoryPressureLevel level) {
-  MemoryPressureControllerImpl::GetInstance()->SendPressureNotification(
-      render_process_host, level);
-}
-
-}  // namespace content