Implement upload progress handling in Mojo loading

content/browser/loader/test_url_loader_client.cc

Index: content/browser/loader/test_url_loader_client.cc
diff --git a/content/browser/loader/test_url_loader_client.cc b/content/browser/loader/test_url_loader_client.cc
index f3720eed23a3eb1643eda1e4ad68517c7156522e..f84d54ab9dfbfbd2315d97b966b5ccff4eeea9d7 100644
--- a/content/browser/loader/test_url_loader_client.cc
+++ b/content/browser/loader/test_url_loader_client.cc
@@ -45,6 +45,12 @@ void TestURLLoaderClient::OnDataDownloaded(int64_t data_length,
     quit_closure_for_on_data_downloaded_.Run();
 }
 
+void TestURLLoaderClient::OnUploadProgress(int64_t current_position,
+                                           int64_t total_size,
+                                           const base::Closure& ack_callback) {
+  ack_callback.Run();
+}
+
 void TestURLLoaderClient::OnStartLoadingResponseBody(
     mojo::ScopedDataPipeConsumerHandle body) {
   response_body_ = std::move(body);