Replace some incorrect details about sizing a flexbox in the layout algorithm with placeholder issues.

Author: tabatkins

css3-flexbox/Overview.html

@@ -1875,15 +1875,17 @@ <h2 id=layout-algorithm><span class=secno>7. </span> Flexbox Layout
      lines:</p>
 
     <ol>
-     <li>Determine the flexbox's available space by finding the size of the
-      flexbox's parent's content box in the flexbox's main axis, and
-      subtracting the size of the flexbox's margins, borders, and padding in
-      the main axis.
+     <li>Determine the main size of the flexbox's content box.
+      <p class=issue>Fill in the details about how to do so when the width is
+       min/max/fit-content. This is complicated for multiline, especially for
+       &lsquo;<code class=css>flex-flow:column</code>&rsquo;!
 
      <li>Collect as many consecutive flexbox items as possible, starting from
       the first item, while keeping the sum of their main size smaller than
-      the flexbox's available space. The items so collected form a single
-      flexbox line.
+      the flexbox's available space. If a flexbox item is sized with a
+      flexible length, then for the purpose of this step, clamp the item's
+      size between its minimum and maximum main sizes. The items so collected
+      form a single flexbox line.
 
      <li>Repeat the previous step, starting each time from the first flexbox
       item not yet collected into a flexbox line, until all flexbox items
@@ -1894,11 +1896,8 @@ <h2 id=layout-algorithm><span class=secno>7. </span> Flexbox Layout
     <p>Find the actual main size of the flexbox, per the standard rules for
      blocks (for block flexboxes) or inline-blocks (for inline flexboxes).</p>
 
-    <p>The min-content, max-content, or fit-content size of a flexbox in the
-     main axis can be determined by, for each flexbox line, summing the
-     min-content, max-content, or fit-content (as appropriate) sizes in the
-     main axis of the flexbox items, and then returning the maximum of these
-     sums.</p>
+    <p class=issue>Address min/max/fix-content here as well. Perhaps just
+     combine this step with the previous?</p>
 
    <li>For each flexbox line, <a
     href="#resolve-the-flexible-lengths"><i>resolve the flexible

css3-flexbox/Overview.src.html

@@ -912,9 +912,11 @@ <h2 id='layout-algorithm'>
 			<p>If the flexbox is multi-line, group the flexbox items into multiple lines:</p>
 
 			<ol>
-				<li>Determine the flexbox's available space by finding the size of the flexbox's parent's content box in the flexbox's main axis, and subtracting the size of the flexbox's margins, borders, and padding in the main axis.</li>
+				<li>Determine the main size of the flexbox's content box.
 
-				<li>Collect as many consecutive flexbox items as possible, starting from the first item, while keeping the sum of their main size smaller than the flexbox's available space.  The items so collected form a single flexbox line.</li>
+				<p class='issue'>Fill in the details about how to do so when the width is min/max/fit-content. This is complicated for multiline, especially for ''flex-flow:column''!</p></li>
+
+				<li>Collect as many consecutive flexbox items as possible, starting from the first item, while keeping the sum of their main size smaller than the flexbox's available space.  If a flexbox item is sized with a flexible length, then for the purpose of this step, clamp the item's size between its minimum and maximum main sizes.  The items so collected form a single flexbox line.</li>
 
 				<li>Repeat the previous step, starting each time from the first flexbox item not yet collected into a flexbox line, until all flexbox items have been collected into flexbox lines.</li>
 			</ol>
@@ -923,7 +925,7 @@ <h2 id='layout-algorithm'>
 		<li>
 			<p>Find the actual main size of the flexbox, per the standard rules for blocks (for block flexboxes) or inline-blocks (for inline flexboxes).</p>
 
-			<p>The min-content, max-content, or fit-content size of a flexbox in the main axis can be determined by, for each flexbox line, summing the min-content, max-content, or fit-content (as appropriate) sizes in the main axis of the flexbox items, and then returning the maximum of these sums.</p>
+			<p class='issue'>Address min/max/fix-content here as well.  Perhaps just combine this step with the previous?</p>
 		</li>
 
 		<li>For each flexbox line, <i>resolve the flexible lengths</i> of the items contained within it.  All flexbox items now have a final main size.  Update each item's hypothetical cross size based on this main size.</li>