Clear baseLayoutStyle when the font selector version has increased.

Source/core/animation/ElementAnimations.cpp

 /*
  * Copyright (C) 2013 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 72 matching lines @@
 
 DEFINE_TRACE(ElementAnimations)
 {
 #if ENABLE(OILPAN)
     visitor->trace(m_cssAnimations);
     visitor->trace(m_defaultStack);
     visitor->trace(m_players);
 #endif
 }
 
-const LayoutStyle* ElementAnimations::baseLayoutStyle() const
+const LayoutStyle* ElementAnimations::validateBaseLayoutStyle()
 {
-#if !ENABLE(ASSERT)
-    if (isAnimationStyleChange())
-        return m_baseLayoutStyle.get();
+    if (!m_baseLayoutStyle)
+        return nullptr;
+
+    if (!isAnimationStyleChange() || !m_baseLayoutStyle->font().isFallbackValid()) {
+        setAnimationStyleChange(false);

[esprehn, 2015/03/26 23:28:15]

This bit may be read in a bunch of places, this would mean it's invalid any time
before this method is called.

We should just make isAnimationStyleChange check check the bit:

isAnimationStyleChange() {
   return ... && (!m_baseLayoutStyle ||
m_baseLayoutStyle->font().isFallbackValid());
}

I think this also requires a TODO/FIXME that explains why we'd need to check
font explicitly since that's pretty weird.

[rune, 2015/03/27 07:14:22]

Yep. Doing this made the patch a lot simpler.

Done.
Done.

+        clearBaseLayoutStyle();
+    }
+#if ENABLE(ASSERT)
+    return nullptr;
+#else
+    return m_baseLayoutStyle.get();
 #endif
-    return nullptr;
 }
 
 void ElementAnimations::updateBaseLayoutStyle(const LayoutStyle* layoutStyle)
 {
     if (!isAnimationStyleChange()) {
         m_baseLayoutStyle = nullptr;
         return;
     }
 #if ENABLE(ASSERT)
     if (m_baseLayoutStyle && layoutStyle)
         ASSERT(*m_baseLayoutStyle == *layoutStyle);
 #endif
     m_baseLayoutStyle = LayoutStyle::clone(*layoutStyle);
 }
 
 void ElementAnimations::clearBaseLayoutStyle()
 {
     m_baseLayoutStyle = nullptr;
 }
 
 } // namespace blink