[css-sizing] Accidentally dropped this paragraph somehow.

Author: tabatkins

css-sizing/Overview.bs

@@ -371,6 +371,11 @@ Intrinsic Sizes of Replaced Elements</h3>
 		of the element,
 		calculated with an unconstrained specified size.
 
+	The <a>min-content contribution</a> and <a>max-content contribution</a> in each axis
+    is the element's specified outer size in that axis, if definite,
+    and the <a>min-content size</a>, as specified above, plus the element's margin/border/padding in that axis otherwise,
+    clamped by the element's min and max size properties in that axis.
+
 <h3 id='inline-intrinsic'>
 Intrinsic Sizes of Non-Replaced Inlines</h3>