diff --git a/dom/bindings/Codegen.py b/dom/bindings/Codegen.py
index 8ee732cca3..8985863e8f 100644
--- a/dom/bindings/Codegen.py
+++ b/dom/bindings/Codegen.py
@@ -1109,6 +1109,12 @@ class CGHeaders(CGWrapper):
         # Now find all the things we'll need as arguments because we
         # need to wrap or unwrap them.
         bindingHeaders = set()
+
+        # KeyframeAnimationOptions.webidl is doing something VERY screwy and
+        # Unified Building really sucks so directly include this
+        if prefix == "KeyframeAnimationOptionsBinding":
+          bindingHeaders.add("mozilla/dom/PrimitiveConversions.h")
+
         declareIncludes = set(declareIncludes)
 
         def addHeadersForType((t, dictionary)):