Popup with Textarea is positioned incorrectly

[pudovika]

Issue description

Textarea in Popup gets unexpected height style and popup moves up on page.

Textareas in popup are not being set height style so setting height style for this textarea is quite unexpected behaviour, because when you have opened popup at first time it appears in wrong possition.

This problem appears in JQM 1.4.0 and higher. Also I noticed that height of textarea depends on count of chars in text (looks like 1 char adds 22px to height).

Test page

http://jsbin.com/vufutenu/1

Steps to reproduce

Click button popup 1.

Expected outcome

Popup is opened in the center of screen.

Actual outcome

Popup opens above center, size of Popup changes after a few seconds. Second time popup open in correct position.

P.S. Looks like it related to this issue #6764

[gabrielschulhof]

The problem is with autogrow, not popup. For some reason it's calculating that the textarea must be much taller than it really has to be.