1 files changed, 3 insertions, 1 deletions
diff --git a/dom/base/nsAttrValue.h b/dom/base/nsAttrValue.h
index 4ef63c287f..b32dfc98fb 100644
--- a/dom/base/nsAttrValue.h
+++ b/dom/base/nsAttrValue.h
@@ -108,7 +108,9 @@ const uintptr_t NS_ATTRVALUE_BASETYPE_MASK = 3;
 class nsCheapString : public nsString {
  public:
   explicit nsCheapString(nsStringBuffer* aBuf) {
-    if (aBuf) aBuf->ToString(aBuf->StorageSize() / sizeof(char16_t) - 1, *this);
+    if (aBuf) {
+      Assign(aBuf, aBuf->StorageSize() / sizeof(char16_t) - 1);
+    }
   }
 };