Find in Page should not consider transparent texts.

Source/core/editing/iterators/TextIterator.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2005 Alexey Proskuryakov.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 432 matching lines @@
         int end = (textNode == m_endContainer) ? m_endOffset : INT_MAX;
         int runEnd = std::min(strLength, end);
 
         if (runStart >= runEnd)
             return true;
 
         emitText(textNode, textNode->layoutObject(), runStart, runEnd);
         return true;
     }
 
+    if (layoutObject->style()->visitedDependentColor(CSSPropertyColor) == Color::transparent)
+        return false;
+
     if (layoutObject->firstTextBox())
         m_textBox = layoutObject->firstTextBox();
 
     bool shouldHandleFirstLetter = !m_handledFirstLetter && layoutObject->isTextFragment() && !m_offset;
     if (shouldHandleFirstLetter)
         handleTextNodeFirstLetter(toLayoutTextFragment(layoutObject));
 
     if (!layoutObject->firstTextBox() && str.length() > 0 && !shouldHandleFirstLetter) {
         if (layoutObject->style()->visibility() != VISIBLE && !ignoresStyleVisibility())
             return false;
@@ skipping 638 matching lines @@
 
 String plainText(const PositionInComposedTree& start, const PositionInComposedTree& end, TextIteratorBehaviorFlags behavior)
 {
     return createPlainText<EditingInComposedTreeStrategy>(start, end, behavior);
 }
 
 template class CORE_TEMPLATE_EXPORT TextIteratorAlgorithm<EditingStrategy>;
 template class CORE_TEMPLATE_EXPORT TextIteratorAlgorithm<EditingInComposedTreeStrategy>;
 
 } // namespace blink