WEB-6807 Emmet: expanding CSS property that starts with 's' with vendor prefix results in incorrect property name

xml/impl/src/com/intellij/application/options/emmet/CssPrefixInfo.java

@@ -94,6 +94,14 @@ public class CssPrefixInfo {
     return result;
   }
 
+  @Override
+  public String toString() {
+    return "CssPrefixInfo{" +
+           "myPropertyName='" + myPropertyName + '\'' +
+           ", myEnabledPrefixes=" + myEnabledPrefixes +
+           '}';
+  }
+
   @Override
   public boolean equals(Object o) {
     if (this == o) return true;