Audit the use of updateStyleAndLayoutIgnorePendingStylesheets in SearchBuffer.

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 1942 matching lines @@
     UseCounter::count(frame(), UseCounter::ExternalAddSearchProvider);
 }
 
 void WebLocalFrameImpl::didCallIsSearchProviderInstalled()
 {
     UseCounter::count(frame(), UseCounter::ExternalIsSearchProviderInstalled);
 }
 
 bool WebLocalFrameImpl::find(int identifier, const WebString& searchText, const WebFindOptions& options, bool wrapWithinFrame, WebRect* selectionRect, bool* activeNow)
 {
+    // TODO(dglazkov): This is a bit silly, since isFocused asks the same questions, but we'll keep it here
+    // to make the next condition less tangled.
+    if (!frame() || !frame()->page())

[esprehn, 2016/07/22 05:57:10]

I wonder how you get a frame without a page? Is this just checking
isLocalFrame() ?

[dglazkov, 2016/07/22 16:40:50]

I think that check it bogus. The only time you have Frame::page return nullptr
is after the frame is detached. I hope we don't do something silly like trying
to search a detached iframe. Let me just replace it with a DCHECK.

+        return false;
+
     // Search for an active match only if this frame is focused or if this is a
     // find next request.
-    if (isFocused() || options.findNext)
-        return ensureTextFinder().find(identifier, searchText, options, wrapWithinFrame, selectionRect, activeNow);
+    if (!isFocused() && !options.findNext)
+        return false;
 
-    return false;
+    // Up-to-date, clean tree is required for finding text in page, since it relies
+    // on TextIterator to look over the text.
+    frame()->document()->updateStyleAndLayoutIgnorePendingStylesheets();
+
+    return ensureTextFinder().find(identifier, searchText, options, wrapWithinFrame, selectionRect, activeNow);
 }
 
 void WebLocalFrameImpl::stopFinding(StopFindAction action)
 {
     bool clearSelection = action == StopFindActionClearSelection;
     if (clearSelection)
         executeCommand(WebString::fromUTF8("Unselect"));
 
     if (m_textFinder) {
         if (!clearSelection)
@@ skipping 163 matching lines @@
 {
     frame()->loader().forceSandboxFlags(static_cast<SandboxFlags>(flags));
 }
 
 void WebLocalFrameImpl::clearActiveFindMatch()
 {
     ensureTextFinder().clearActiveFindMatch();
 }
 
 } // namespace blink