Clear baseLayoutStyle when the font selector version has increased.

Source/core/animation/ElementAnimations.cpp

Index: Source/core/animation/ElementAnimations.cpp
diff --git a/Source/core/animation/ElementAnimations.cpp b/Source/core/animation/ElementAnimations.cpp
index 86500eca222de8ac8b5f370b13498a3558e4425b..4af2dcac5c1c8cf2cd7c075b13161899fcb54827 100644
--- a/Source/core/animation/ElementAnimations.cpp
+++ b/Source/core/animation/ElementAnimations.cpp
@@ -90,13 +90,20 @@ DEFINE_TRACE(ElementAnimations)
 #endif
 }
 
-const LayoutStyle* ElementAnimations::baseLayoutStyle() const
+const LayoutStyle* ElementAnimations::validateBaseLayoutStyle()
 {
-#if !ENABLE(ASSERT)
-    if (isAnimationStyleChange())
-        return m_baseLayoutStyle.get();
-#endif
+    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
 }
 
 void ElementAnimations::updateBaseLayoutStyle(const LayoutStyle* layoutStyle)