平台：小米 4、Android 4.4
知乎版本：3.0.1
前置条件：弱网或者无网络

重现步骤：

1. 进入知乎首页查看一个问题详情
2. 弱网或者无网络条件下，在问题详情界面点击 Action Bar 中的菜单按钮，列表中会有一个选项为” 编辑问题 “
3. 点击” 编辑问题 “

结果：应用停止运行，必现。

日志信息：

01-28 09:41:18.153 D/AndroidRuntime(14064): Shutting down VM
01-28 09:41:22.163 E/AndroidRuntime(14064): FATAL EXCEPTION: main
01-28 09:41:22.163 E/AndroidRuntime(14064): Process: com.zhihu.android, PID: 14064
01-28 09:41:22.163 E/AndroidRuntime(14064): java.lang.IllegalArgumentException: String input must not be null
01-28 09:41:22.163 E/AndroidRuntime(14064):     at org.jsoup.helper.Validate.notNull(Validate.java:26)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at org.jsoup.parser.TreeBuilder.initialiseParse(TreeBuilder.java:26)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at org.jsoup.parser.TreeBuilder.parse(TreeBuilder.java:42)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at org.jsoup.parser.HtmlTreeBuilder.parse(HtmlTreeBuilder.java:53)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at org.jsoup.parser.Parser.parse(Parser.java:89)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at org.jsoup.Jsoup.parse(Jsoup.java:58)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at com.zhihu.android.app.ui.fragment.k.b.c(QuestionOldEditFragment.java:1633)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at com.zhihu.android.app.ui.fragment.k.b.k(QuestionOldEditFragment.java:544)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at com.zhihu.android.app.ui.fragment.k.b.g(QuestionOldEditFragment.java:487)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at com.zhihu.android.app.ui.fragment.k.b.onViewCreated(QuestionOldEditFragment.java:299)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at android.support.v4.app.q.a(FragmentManager.java:1086)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at android.support.v4.app.q.a(FragmentManager.java:1248)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at android.support.v4.app.h.run(BackStackRecord.java:738)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at android.support.v4.app.q.h(FragmentManager.java:1613)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at android.support.v4.app.q$1.run(FragmentManager.java:517)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at android.os.Handler.handleCallback(Handler.java:733)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at android.os.Handler.dispatchMessage(Handler.java:95)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at android.os.Looper.loop(Looper.java:136)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at android.app.ActivityThread.main(ActivityThread.java:5072)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at java.lang.reflect.Method.invokeNative(Native Method)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at java.lang.reflect.Method.invoke(Method.java:515)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
01-28 09:41:22.163 E/AndroidRuntime(14064):     at dalvik.system.NativeStart.main(Native Method)