Fixing a number of dart:html analyzer issues

sdk/lib/html/html_common/lists.dart

Index: sdk/lib/html/html_common/lists.dart
diff --git a/sdk/lib/html/html_common/lists.dart b/sdk/lib/html/html_common/lists.dart
index 03cc29e5ccded15e85c4bd2d2a90906cdab186f5..874039e05c399191c8ad71b4121c87cc844c9217 100644
--- a/sdk/lib/html/html_common/lists.dart
+++ b/sdk/lib/html/html_common/lists.dart
@@ -66,22 +66,4 @@ class Lists {
     }
     return accumulator;
   }
-
-  static String join(List<Object> list, [String separator]) {
-    if (list.isEmpty) return "";
-    if (list.length == 1) return "${list[0]}";
-    StringBuffer buffer = new StringBuffer();
-    if (separator == null || separator == "") {
-      for (int i = 0; i < list.length; i++) {
-        buffer.add("${list[i]}");
-      }
-    } else {
-      buffer.add("${list[0]}");
-      for (int i = 1; i < list.length; i++) {
-        buffer.add(separator);
-        buffer.add("${list[i]}");
-      }
-    }
-    return buffer.toString();
-  }
 }