Use process/control messages (instead of RVH messages) for layout tests.

content/shell/common/layout_test/layout_test_content_client.cc

Index: content/shell/common/layout_test/layout_test_content_client.cc
diff --git a/content/shell/common/layout_test/layout_test_content_client.cc b/content/shell/common/layout_test/layout_test_content_client.cc
deleted file mode 100644
index 404eebf8aeafb90a35863e459c2377bc8dd5bfed..0000000000000000000000000000000000000000
--- a/content/shell/common/layout_test/layout_test_content_client.cc
+++ /dev/null
@@ -1,23 +0,0 @@
-// 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/shell/common/layout_test/layout_test_content_client.h"
-
-#include "content/shell/common/shell_messages.h"
-
-namespace content {
-
-bool LayoutTestContentClient::CanSendWhileSwappedOut(
-    const IPC::Message* message) {
-  switch (message->type()) {
-    // Used in layout tests; handled in BlinkTestController.
-    case ShellViewHostMsg_PrintMessage::ID:
-      return true;
-
-    default:
-      return false;
-  }
-}
-
-}  // namespace content