feat: allow override onProgress on Upload (#5260)

@see https://github.com/react-component/upload/issues/33#issuecomment-284644039

components/upload/index.tsx

@@ -267,12 +267,13 @@ export default class Upload extends React.Component<UploadProps, any> {
       type, disabled, children, className,
     } = this.props;
 
-    const rcUploadProps = assign({}, this.props, {
+    const rcUploadProps = assign({}, {
       onStart: this.onStart,
       onError: this.onError,
       onProgress: this.onProgress,
       onSuccess: this.onSuccess,
-    });
+    }, this.props);
+
     delete rcUploadProps.className;
 
     const { showRemoveIcon, showPreviewIcon } = showUploadList as any;

components/upload/uploadList.tsx

@@ -94,9 +94,14 @@ export default class UploadList extends React.Component<UploadListProps, any> {
       }
 
       if (file.status === 'uploading') {
+        // show loading icon if upload progress listener is disabled
+        const loadingProgress = file.percent ? (
+          <Progress type="line" {...this.props.progressAttr} percent={file.percent} />
+        ) : <Icon type="loading" />;
+
         progress = (
           <div className={`${prefixCls}-list-item-progress`}>
-            <Progress type="line" {...this.props.progressAttr} percent={file.percent} />
+            {loadingProgress}
           </div>
         );
       }