[FastTextAutosizer] Remove comment about storing a fingerprint stack

Source/core/rendering/FastTextAutosizer.cpp

Index: Source/core/rendering/FastTextAutosizer.cpp
diff --git a/Source/core/rendering/FastTextAutosizer.cpp b/Source/core/rendering/FastTextAutosizer.cpp
index 5cbbf1bd02c399e5b79e4b740fb5611d8b3f28eb..3f0f5573fecb952b4728169817acdf3908740cdd 100644
--- a/Source/core/rendering/FastTextAutosizer.cpp
+++ b/Source/core/rendering/FastTextAutosizer.cpp
@@ -535,11 +535,6 @@ FastTextAutosizer::Fingerprint FastTextAutosizer::computeFingerprint(const Rende
         return 0;
 
     FingerprintSourceData data;
-
-    // FIXME: Instead of computing and caching parent fingerprints on demand,
-    // consider maintaining a fingerprint stack during the style recalc
-    // tree walk (similar to the cluster stack used during layout).
-
     if (const RenderObject* parent = parentElementRenderer(renderer))
         data.m_parentHash = getFingerprint(parent);