More strict restrictions for content -> content/shell dependencies.

content/shell/common/layout_test/layout_test_content_client.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/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:
+    case ShellViewHostMsg_LayoutDumpFlagsChanged::ID:
+      return true;
+
+    default:
+      return false;
+  }
+}
+
+}  // namespace content