Add hooks for capturing meaningful text info, gently.

Source/web/WebLocalFrameImpl.h

 /*
  * 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 228 matching lines @@
     void setDevToolsAgentClient(WebDevToolsAgentClient*) override;
     WebDevToolsAgent* devToolsAgent() override;
     void sendPings(const WebNode& contextNode, const WebURL& destinationURL) override;
     WebURLRequest requestFromHistoryItem(const WebHistoryItem&, WebURLRequest::CachePolicy)
         const override;
     WebURLRequest requestForReload(WebFrameLoadType, const WebURL&) const override;
     void load(const WebURLRequest&, WebFrameLoadType, const WebHistoryItem&,
         WebHistoryLoadType) override;
     bool isLoading() const override;
     bool isResourceLoadInProgress() const override;
+    bool isNavigationScheduled() const override;
     void setCommittedFirstRealLoad() override;
     void sendOrientationChangeEvent() override;
     void willShowInstallBannerPrompt(int requestId, const WebVector<WebString>& platforms, WebAppBannerPromptReply*) override;
     WebSandboxFlags effectiveSandboxFlags() const override;
     void requestRunTask(WebSuspendableTask*) const override;
 
     void willBeDetached();
     void willDetachParent();
 
     static WebLocalFrameImpl* create(WebTreeScopeType, WebFrameClient*);
@@ skipping 141 matching lines @@
     // cleared upon close().
     SelfKeepAlive<WebLocalFrameImpl> m_selfKeepAlive;
 #endif
 };
 
 DEFINE_TYPE_CASTS(WebLocalFrameImpl, WebFrame, frame, frame->isWebLocalFrame(), frame.isWebLocalFrame());
 
 } // namespace blink
 
 #endif