Prevent guest views from issuing a search for empty text.

android_webview/browser/find_helper.h

 // Copyright (c) 2012 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.
 
 #ifndef ANDROID_WEBVIEW_BROWSER_FIND_HELPER_H_
 #define ANDROID_WEBVIEW_BROWSER_FIND_HELPER_H_
 
-#include "base/memory/weak_ptr.h"
 #include "content/public/browser/web_contents_observer.h"
 
 namespace android_webview {
 
 // Handles the WebView find-in-page API requests.
 class FindHelper : public content::WebContentsObserver {
  public:
   class Listener {
    public:
     // Called when receiving a new find-in-page update.
     // This will be triggered when the results of FindAllSync, FindAllAsync and
     // FindNext are available. The value provided in active_ordinal is 0-based.
     virtual void OnFindResultReceived(int active_ordinal,
                                       int match_count,
                                       bool finished) = 0;
     virtual ~Listener() {}
   };
 
   explicit FindHelper(content::WebContents* web_contents);
   ~FindHelper() override;
 
   // Sets the listener to receive find result updates.
-  // Does not own the listener and must set to NULL when invalid.
+  // Does not own the listener and must set to nullptr when invalid.
   void SetListener(Listener* listener);
 
   // Asynchronous API.
   void FindAllAsync(const base::string16& search_string);
   void HandleFindReply(int request_id,
                        int match_count,
                        int active_ordinal,
                        bool finished);
 
   // Methods valid in both synchronous and asynchronous modes.
   void FindNext(bool forward);
   void ClearMatches();
 
  private:
   void StartNewRequest(const base::string16& search_string);
+  bool MaybeHandleEmptySearch(const base::string16& search_string);
   void NotifyResults(int active_ordinal, int match_count, bool finished);
 
   // Listener results are reported to.
   Listener* listener_;
 
   // Used to check the validity of FindNext operations.
   bool async_find_started_;
-  bool sync_find_started_;
 
   // Used to provide different ids to each request and for result
   // verification in asynchronous calls.
   int find_request_id_counter_;
   int current_request_id_;
 
   // Required by FindNext and the incremental find replies.
   base::string16 last_search_string_;
   int last_match_count_;
   int last_active_ordinal_;
 
-  // Used to post synchronous result notifications to ourselves.
-  base::WeakPtrFactory<FindHelper> weak_factory_;
-
   DISALLOW_COPY_AND_ASSIGN(FindHelper);
 };
 
 }  // namespace android_webview
 
 #endif  // ANDROID_WEBVIEW_BROWSER_FIND_HELPER_H_