[css-grid-2] Remove issue about masonry layout; discussion is happeni…

…ng in #945 and it's not entirely clear it's a Grid issue.

css-grid-2/Overview.bs

@@ -362,50 +362,3 @@ Aspect-ratio&ndash;controlled Gutters</h2>
 			}
 		</pre>
 	</div>
-
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-
-<h2 id=masonry>
-Masonry Layout</h2>
-
-<div class=issue>
-	People have been trying to use CSS for <a href="https://github.com/w3c/csswg-drafts/issues/1009#issuecomment-278095001">masonry layouts</a> for over a decade,
-	and it doesn't seem to have slowed,
-	so it's probably not just a layout fad.
-	Would probably be worthwhile to address officially.
-
-	As far as I can tell,
-	this is best done as a Grid feature;
-	some of the features I've seen in masonry libraries
-	(like large items spanning multiple masonry tracks)
-	make Flexbox inappropriate.
-	This also would reuse *so many* Grid features
-	that it would be a shame to put together a brand new layout spec for it.
-
-	No clue what it would look like yet, tho.
-	In handwavey terms, it's a grid that's only gridded
-	"in one dimension",
-	and free-flows in the other,
-	with auto-flow.
-
-	Note that this is actually 100% possibly with Grid today,
-	if your items are of known height,
-	by making thousands of 1px tall rows,
-	and setting the items' row-span to be equal to their height in px.
-	(Or some lower-res multiple, like 10px rows.)
-	Dense row auto-flow then magically makes Masonry happen.
-	This is just a terrible hack that runs into memory/CPU issues
-	due to the large number of rows.
-	It suggests, tho,
-	that making it work properly
-	is mostly a matter of relaxing some constraints,
-	rather than adding entirely new behavior.
-</div>