diff --git a/dom/smil/nsSMILCSSValueType.cpp b/dom/smil/nsSMILCSSValueType.cpp
index 85fe72085eac..8e8a916caf04 100644
--- a/dom/smil/nsSMILCSSValueType.cpp
+++ b/dom/smil/nsSMILCSSValueType.cpp
@@ -417,6 +417,34 @@ nsSMILCSSValueType::ValueFromString(nsCSSPropertyID aPropID,
   }
 }
 
+// static
+nsSMILValue
+nsSMILCSSValueType::ValueFromAnimationValue(nsCSSPropertyID aPropID,
+                                            Element* aTargetElement,
+                                            const StyleAnimationValue& aValue)
+{
+  nsSMILValue result;
+
+  nsIDocument* doc = aTargetElement->GetUncomposedDoc();
+  // We'd like to avoid serializing |aValue| if possible, and since the
+  // string passed to CSPAllowsInlineStyle is only used for reporting violations
+  // and an intermediate CSS value is not likely to be particularly useful
+  // in that case, we just use a generic placeholder string instead.
+  static const nsLiteralString kPlaceholderText =
+    NS_LITERAL_STRING("[SVG animation of CSS]");
+  if (doc && !nsStyleUtil::CSPAllowsInlineStyle(nullptr,
+                                                doc->NodePrincipal(),
+                                                doc->GetDocumentURI(),
+                                                0, kPlaceholderText, nullptr)) {
+    return result;
+  }
+
+  sSingleton.Init(result);
+  result.mU.mPtr = new ValueWrapper(aPropID, aValue);
+
+  return result;
+}
+
 // static
 bool
 nsSMILCSSValueType::ValueToString(const nsSMILValue& aValue,
diff --git a/dom/smil/nsSMILCSSValueType.h b/dom/smil/nsSMILCSSValueType.h
index 0c71605f0576..f244639010b3 100644
--- a/dom/smil/nsSMILCSSValueType.h
+++ b/dom/smil/nsSMILCSSValueType.h
@@ -16,6 +16,7 @@
 class nsAString;
 
 namespace mozilla {
+class StyleAnimationValue;
 namespace dom {
 class Element;
 } // namespace dom
@@ -28,6 +29,7 @@ class nsSMILCSSValueType : public nsISMILType
 {
 public:
   typedef mozilla::dom::Element Element;
+  typedef mozilla::StyleAnimationValue StyleAnimationValue;
 
   // Singleton for nsSMILValue objects to hold onto.
   static nsSMILCSSValueType sSingleton;
@@ -84,6 +86,21 @@ public:
                               nsSMILValue& aValue,
                               bool* aIsContextSensitive);
 
+  /**
+   * Creates an nsSMILValue to wrap the given animation value.
+   *
+   * @param aPropID         The property that |aValue| corresponds to.
+   * @param aTargetElement  The target element to which the animation value
+   *                        applies.
+   * @param aValue          The animation value to use.
+   * @return                A new nsSMILValue. On failure, returns an
+   *                        nsSMILValue with the null type (i.e. rv.IsNull()
+   *                        returns true).
+   */
+  static nsSMILValue ValueFromAnimationValue(nsCSSPropertyID aPropID,
+                                             Element* aTargetElement,
+                                             const StyleAnimationValue& aValue);
+
   /**
    * Creates a string representation of the given nsSMILValue.
    *