--- a/layout/style/ComputedStyle.cpp
+++ b/layout/style/ComputedStyle.cpp
@@ -343,17 +343,17 @@ ComputedStyle::CalcStyleDifference(Compu
   }
 
   MOZ_ASSERT(NS_IsHintSubset(hint, nsChangeHint_AllHints),
              "Added a new hint without bumping AllHints?");
   return hint & ~nsChangeHint_NeutralChange;
 }
 
 #ifdef DEBUG
-void ComputedStyle::List(FILE* out, int32_t aIndent, bool)
+void ComputedStyle::List(FILE* out, int32_t aIndent)
 {
   nsAutoCString str;
   // Indent
   int32_t ix;
   for (ix = aIndent; --ix >= 0; ) {
     str.AppendLiteral("  ");
   }
   str.Append(nsPrintfCString("%p(%d) parent=%p ",

--- a/layout/style/ComputedStyle.h
+++ b/layout/style/ComputedStyle.h
@@ -340,17 +340,17 @@ public:
     MOZ_ASSERT(0 <= aSID && aSID < nsStyleStructID_Length,
                "must be an inherited or reset SID");
     return nsStyleStructID_Reset_Start <= aSID;
   }
   static bool IsInherited(const nsStyleStructID aSID) { return !IsReset(aSID); }
   static uint32_t GetBitForSID(const nsStyleStructID aSID) { return 1 << aSID; }
 
 #ifdef DEBUG
-  void List(FILE* out, int32_t aIndent, bool aListDescendants = true);
+  void List(FILE* out, int32_t aIndent);
   static const char* StructName(nsStyleStructID aSID);
   static bool LookupStruct(const nsACString& aName, nsStyleStructID& aResult);
 #endif
 
   /**
    * Makes this context match |aOther| in terms of which style structs have
    * been resolved.
    */