[4.1-rc1] Strange behaviour of DatePicker placing in Panel with vbox layout

[vietits]

Ext version tested:

• Ext 4.1-rc1

Browser versions tested against:

• Chrome 17

DOCTYPE tested against:

• ____

Description:

• The DatePicker changes its width instead of keeping stretch to its parent width when changing month by clicking Previous Month/Next Month buttons or Month/Year dropdown.
  This only happens when setting the height of DatePicker to a specific value. If setting it to null or not setting it then the DatePicker works as expect.

Steps to reproduce the problem:

• open the testing code in browser
• Change the month by clicking Previous Month or Next Month button or Month/Year dropdown

The result that was expected:

• The DatePicker must keep its width stretched to its parent width.

The result that occurs instead:

• The DatePicker change its width

Test Case:

Ext.require([
    'Ext.*'
]);


Ext.onReady( function(){
    Ext.create('Ext.panel.Panel',{
        renderTo: Ext.getBody(),
        width: 400,
        height: 300,
        layout: {
            type: 'vbox',
            align: 'stretch'
        },
        items: [{
            xtype: 'datepicker',
            height: 200 // <- No problem if height is null
        }]
    });
});

Debugging already done:

• none

Possible fix:

• not provided

Additional CSS used:

• only default ext-all.css

Operating System:

• Win 7 - 32bit

[mitchellsimoens]

Looks like this has happened in all 4.1.0 releases, worked in 4.0.7 so a regression.