compatible for requests without protocol such as tieba.baidu.com, if not,many css files will be lost.

The unfixed version cause the following error

```
I/ProxyService(25480): Request 24 GET http://tb2.bdstatic.com/??/tb/mobile/carousel_e27119f.css,/tb/mobile/post_item_7a4e9df.css,/tb/mobile/new_feed_86dc9de.css,/tb/mobile/recommend_forum_card_4567de1.css,/tb/mobile/recommend_forum_323a891.css,/tb/mobile/daily_posts_008c9bd.css,/tb/mobile/login_regist_e7a3763.css,/tb/mobile/pic_free_mode_adapter_1707228.css,/tb/mobile/common_resources_890c030.css,/tb/mobile/pager_c93d7fc.css,/tb/mobile/search_cf19618.css,/tb/mobile/top_bar_1f104d8.css,/tb/mobile/tab_head_0eff868.css,/tb/mobile/app_detail_cba43c9.css,/tb/mobile/track_view_1e5241a.css,/tb/mobile/client_ad_top_third_party_faa4c60.css,/tb/mobile/client_ad_top_2b8f5be.css,/tb/mobile/footer_ab767b0.css,/tb/mobile/client_bottom_tip_250dad6.css,/tb/mobile/client_ghost_icon_2f6368d.css,/tb/mobile/tab_con_search_16c45d2.css,/tb/mobile/forum_tile_ae75d80.css,/tb/mobile/recent_browse_d41d8cd.css,/tb/mobile/my_like_95a05e2.css,/tb/mobile/user_info_21a5bba.css,/tb/mobile/no_login_4a005e3.css,/tb/mobile/user_entrance_70b63b0.css,/tb/mobile/index_b27cb30.css
I/global  (25480): NoSuchElementException will happen in nextToken(), string.length= 1024  position= 1024  i= 1024
D/libc    (25480): [NET] getaddrinfo+,hn 16(0x7462322e626473),sn(),family 0,flags 4
I/Error   (25480): 400 Bad Request: GET http://tb2.bdstatic.com/??/tb/mobile/carousel_e27119f.css,/tb/mobile/post_item_7a4e9df.css,/tb/mobile/new_feed_86dc9de.css,/tb/mobile/recommend_forum_card_4567de1.css,/tb/mobile/recommend_forum_323a891.css,/tb/mobile/daily_posts_008c9bd.css,/tb/mobile/login_regist_e7a3763.css,/tb/mobile/pic_free_mode_adapter_1707228.css,/tb/mobile/common_resources_890c030.css,/tb/mobile/pager_c93d7fc.css,/tb/mobile/search_cf19618.css,/tb/mobile/top_bar_1f104d8.css,/tb/mobile/tab_head_0eff868.css,/tb/mobile/app_detail_cba43c9.css,/tb/mobile/track_view_1e5241a.css,/tb/mobile/client_ad_top_third_party_faa4c60.css,/tb/mobile/client_ad_top_2b8f5be.css,/tb/mobile/footer_ab767b0.css,/tb/mobile/client_bottom_tip_250dad6.css,/tb/mobile/client_ghost_icon_2f6368d.css,/tb/mobile/tab_con_search_16c45d2.css,/tb/mobile/forum_tile_ae75d80.css,/tb/mobile/recent_browse_d41d8cd.css,/tb/mobile/my_like_95a05e2.css,/tb/mobile/user_info_21a5bba.css,/tb/mobile/no_login_4a005e3.css,/tb/mobile/user_entrance_70b63b0.css,/tb/mobile/index_b27cb30.css
```