Fix a crash when the content type of a multipart request

webkit/glue/weburlloader_impl.cc

Index: webkit/glue/weburlloader_impl.cc
diff --git a/webkit/glue/weburlloader_impl.cc b/webkit/glue/weburlloader_impl.cc
index 4261f0fa14ec199c45c9ed901e02c9615c0c60b6..8800d6a99a9a8ee7e09ae8a0dec85017dfd9551f 100644
--- a/webkit/glue/weburlloader_impl.cc
+++ b/webkit/glue/weburlloader_impl.cc
@@ -270,7 +270,8 @@ void WebURLLoaderImpl::Context::Cancel() {
 
   // Ensure that we do not notify the multipart delegate anymore as it has
   // its own pointer to the client.
-  multipart_delegate_.reset();
+  if (multipart_delegate_.get())
+    multipart_delegate_->Cancel();
 
   // Do not make any further calls to the client.
   client_ = NULL;