Add enables consistent with Chrome's WebKit

client/dom/generated/src/wrapping/_BlobWrappingImplementation.dart

Index: client/dom/generated/src/wrapping/_BlobWrappingImplementation.dart
diff --git a/client/dom/generated/src/wrapping/_BlobWrappingImplementation.dart b/client/dom/generated/src/wrapping/_BlobWrappingImplementation.dart
index f17c9b2a8098d3eb114411dcc2abd36be2ca9a56..cd834c4834ba824090738eb2fa0ca361c976d4d8 100644
--- a/client/dom/generated/src/wrapping/_BlobWrappingImplementation.dart
+++ b/client/dom/generated/src/wrapping/_BlobWrappingImplementation.dart
@@ -17,5 +17,32 @@ class _BlobWrappingImplementation extends DOMWrapperBase implements Blob {
   String get type() { return _get_type(this); }
   static String _get_type(var _this) native;
 
+  Blob webkitSlice([int start = null, int end = null, String contentType = null]) {
+    if (start === null) {
+      if (end === null) {
+        if (contentType === null) {
+          return _webkitSlice(this);
+        }
+      }
+    } else {
+      if (end === null) {
+        if (contentType === null) {
+          return _webkitSlice_2(this, start);
+        }
+      } else {
+        if (contentType === null) {
+          return _webkitSlice_3(this, start, end);
+        } else {
+          return _webkitSlice_4(this, start, end, contentType);
+        }
+      }
+    }
+    throw "Incorrect number or type of arguments";
+  }
+  static Blob _webkitSlice(receiver) native;
+  static Blob _webkitSlice_2(receiver, start) native;
+  static Blob _webkitSlice_3(receiver, start, end) native;
+  static Blob _webkitSlice_4(receiver, start, end, contentType) native;
+
   String get typeName() { return "Blob"; }
 }