[css-flexbox] Incorrect initial values #3636
Description
CSS Flexible Box Layout Module Level 1 states that the initial value for align-content is stretch. Browsers and CSS Box Alignment Module Level 3 give the initial value as 'normal'.
CSS Flexible Box Layout Module Level 1 states that the initial value for align-items is stretch. Browsers and CSS Box Alignment Module Level 3 give the initial value as 'normal'.
CSS Flexible Box Layout Module Level 1 states that the initial value for justify-content is flex-start. Browsers and CSS Box Alignment Module Level 3 give the initial value as 'normal'.