User can change password without knowing the old password

• Fix Build Number:

  RB-8.4.1.1xxx

User can change password without knowing the old password.

[Repro Steps]
1) create a host with password is "nhn123456" and login.
2) click to edit the host password tobe "zyy123456"(that host will keep login status)
3) and then click for change Password,
if input "nhn123456" for old password, error shows:The old password is not valid
if input "zyy123456", message for successful change will shows.
In this way,user can change password, without knowing the old password is "nhn123456"

[expect result]
I think "Edit Host password" should not do any change to the password for manager<->server
old password should be "nhn123456" after repro step 2).
but now at page "change password", old password is recognized as password in "host information"
In this way, user can change password,without knowing the old password,