Reland r172943 "Make CSSFontFace::willUseFontData() load fonts with unicode-range"

Source/core/rendering/RenderText.cpp

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Andrew Wellington (proton@wiretapped.net)
  * Copyright (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 187 matching lines @@
         setNeedsLayoutAndPrefWidthsRecalc();
         m_knownToHaveNoOverflowAndNoFallbackFonts = false;
     }
 
     RenderStyle* newStyle = style();
     ETextTransform oldTransform = oldStyle ? oldStyle->textTransform() : TTNONE;
     ETextSecurity oldSecurity = oldStyle ? oldStyle->textSecurity() : TSNONE;
     if (oldTransform != newStyle->textTransform() || oldSecurity != newStyle->textSecurity())
         transformText();
 
+    // This is an optimization that kicks off font load before layout.
+    // In order to make it fast, we only check if the first character of the
+    // text is included in the unicode ranges of the fonts.
     if (!text().containsOnlyWhitespace())
-        newStyle->font().willUseFontData();
+        newStyle->font().willUseFontData(text().characterStartingAt(0));
 }
 
 void RenderText::removeAndDestroyTextBoxes()
 {
     if (!documentBeingDestroyed()) {
         if (firstTextBox()) {
             if (isBR()) {
                 RootInlineBox* next = firstTextBox()->root().nextRootBox();
                 if (next)
                     next->markDirty();
@@ skipping 1645 matching lines @@
     }
     secureTextTimer->restartWithNewText(lastTypedCharacterOffset);
 }
 
 PassRefPtr<AbstractInlineTextBox> RenderText::firstAbstractInlineTextBox()
 {
     return AbstractInlineTextBox::getOrCreate(this, m_firstTextBox);
 }
 
 } // namespace WebCore