Implement `direction` property (#906)
1<test name="margin_with_sibling_row__content_box_ltr" use-rounding="true">
2 <viewport width="max-content" height="max-content"/>
3 <input>
4 <div box-sizing="content-box" direction="ltr" width="100px" height="100px">
5 <div box-sizing="content-box" direction="ltr" flex-grow="1" margin-right="10px"/>
6 <div box-sizing="content-box" direction="ltr" flex-grow="1"/>
7 </div>
8 </input>
9 <expectations>
10 <node x="0" y="0" width="100" height="100">
11 <node x="0" y="0" width="45" height="100"/>
12 <node x="55" y="0" width="45" height="100"/>
13 </node>
14 </expectations>
15</test>