如若参数和路由均无变化，不需要调用 init，否则与 keep-alive 功能相矛盾了

iview-admin 很好的处理了标签页切换而状态保持的问题，也提供了带参数页面的 demo，但实际项目中带参数的页面往往是有表单输入的，比如『编辑』页面，这时如果改动了输入框内容，而未保存时切换页签，会触发`$route`的`watch`或者`activated`中的`init()`，所以这里是否该加以判断，只有当路由及参数变化时才去触发 init 呢？否则对于表单页面 keep-alive 就无意义了。

Start by locating the page components that use the $route watch or activated hook to call init(), then inspect how keep-alive handles tab changes. Reproduce the unsaved-form scenario and compare it with a route or parameter change. Done means init() is skipped when both are unchanged while still running when either changes.

Written by the indexing model from the issue text.