[css-flexbox] Remove the redundant first bullet point (changing it to a note), and genericize the third accordingly. w3c#3531

Author: tabatkins

css-flexbox-1/Overview.bs

@@ -2965,12 +2965,6 @@ Definite and Indefinite Sizes</h3>
 	Flexbox has several additional cases where a length can be considered <dfn noexport lt="definite|definite size|indefinite|indefinite size">definite</dfn>:
 
 	<ol>
-		<li>
-			If a <a>single-line</a> <a>flex container</a> has a definite <a>cross size</a>,
-			the outer <a>cross size</a> of any <a>stretched</a> <a>flex items</a>
-			is the flex container's inner <a>cross size</a> (clamped to the <a>flex item</a>’s min and max <a>cross size</a>)
-			and is considered <a>definite</a>.
-
 		<li>
 			If the <a>flex container</a> has a <a>definite</a> <a>main size</a>,
 			a <a>flex item</a>’s post-flexing <a>main size</a>
@@ -2980,9 +2974,14 @@ Definite and Indefinite Sizes</h3>
 
 		<li>
 			Once the cross size of a flex line has been determined,
-			the cross sizes of items in auto-sized flex containers
-			are also considered definite for the purpose of layout;
+			the cross sizes of items in that line
+			are treated as [=definite=] for the purpose of layout;
 			see <a href="#algo-stretch">step 11</a>.
+
+			Note: If a <a>single-line</a> <a>flex container</a> has a definite <a>cross size</a>,
+			the outer <a>cross size</a> of any <a>stretched</a> <a>flex items</a>
+			is the flex container's inner <a>cross size</a> (clamped to the <a>flex item</a>’s min and max <a>cross size</a>)
+			and is always considered <a>definite</a>.
 	</ol>
 
 	Note: The main size of a <a>fully inflexible</a> item with a <a>definite</a> <a>flex basis</a>