Revert of Require WebLocalFrame to be created with a non-null client

third_party/WebKit/Source/web/WebLocalFrameImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 1460 matching lines @@
     : WebLocalFrame(scope)
     , m_frameLoaderClientImpl(FrameLoaderClientImpl::create(this))
     , m_frameWidget(0)
     , m_client(client)
     , m_autofillClient(0)
     , m_contentSettingsClient(0)
     , m_inputEventsScaleFactorForEmulation(1)
     , m_webDevToolsFrontend(0)
     , m_selfKeepAlive(this)
 {
-    DCHECK(m_client);
     frameCount++;
 }
 
 WebLocalFrameImpl::WebLocalFrameImpl(WebRemoteFrame* oldWebFrame, WebFrameClient* client)
     : WebLocalFrameImpl(oldWebFrame->inShadowTree() ? WebTreeScopeType::Shadow : WebTreeScopeType::Document, client)
 {
 }
 
 WebLocalFrameImpl::~WebLocalFrameImpl()
 {
@@ skipping 754 matching lines @@
         feature = UseCounter::ChromeLoadTimesNpnNegotiatedProtocol;
     } else if (metric == "wasAlternateProtocolAvailable") {
         feature = UseCounter::ChromeLoadTimesWasAlternateProtocolAvailable;
     } else if (metric == "connectionInfo") {
         feature = UseCounter::ChromeLoadTimesConnectionInfo;
     }
     UseCounter::count(frame(), feature);
 }
 
 } // namespace blink