[css-multicol] Clarify the section on Pagination and Overflow Outside Multicol Containers

[rachelandrew]

In working through the spec to make edits for #12593 (comment) I need to clarify the section on overflow. We touched on most of this during the fact to face conversation. I think in the scenario where you have a height on the multicol container, overflow columns are still overflow columns even if they wrap so we just need to clarify this section to include the wrapping situation. Proposed edits follow.

A multicol container can have more columns than it has room for due to:

	<ul>
		<li>
			a declaration that constrains the column height
			(e.g., using 'height' or 'max-height').
			In this case, additional column boxes are created in the inline direction
		</li>
		<li>
			the size of the page.
			In this case, additional column boxes are moved to the next page(s).
		</li>
		<li>
			explicit column breaks.
			In this case, additional column boxes are created in the inline direction for continuous contexts
			and additional column boxes are moved to the next fragment(s) for fragmented media.
		<li>
	</ul>

I propose to update this to the following, which I believe reflects discussion at the August f2f.

• In the first bullet changing column height to multicol container height, as this is the height this section refers to (as there was no column-height in multicol-1.).
• Also in the first bullet changing "In this case, additional column boxes are created in the inline direction" to "In this case, additional column boxes are created in the wrapping direction (by default, the inline direction)." This would be less clumsy if we resolve to keep the column-wrap property as we could then say, "in the direction set by the value of column-wrap".
• Similarly clarify the final bullet to remove the mention of continuous contexts.

A multicol container can have more columns than it has room for due to:

	<ul>
		<li>
			a declaration that constrains the multicol container height
			(e.g., using 'height' or 'max-height').
			In this case, additional column boxes are created in the wrapping direction (by default, the inline direction).
		</li>
		<li>
			the size of the page.
			In this case, additional column boxes are moved to the next page(s).
		</li>
		<li>
			explicit column breaks.
			In this case, additional column boxes are created in the in the wrapping direction (by default, the inline direction for continuous contexts).
			and additional column boxes are moved to the next fragment(s) for fragmented media.
		<li>
	</ul>

[css-meeting-bot]

The CSS Working Group just discussed [css-multicol] Clarify the section on Pagination and Overflow Outside Multicol Containers, and agreed to the following:

• RESOLVED: accept Rachel's text/direction

The full IRC log of that discussion

<TabAtkins> rachelandrew: we've made various resolutions, i'm having to make all the rest of the text makes sense now that we have column rows
<florian> q?
<TabAtkins> rachelandrew: I've written in the issue what's there at the moment and what i'm suggesting
<TabAtkins> rachelandrew: this is a change in normative text, so getting verified
<TabAtkins> florian: looks right. we're generalizing the concept, so things need generalization. looks good
<TabAtkins> fantasai: needs better lienbreaks, but otherwise looks good
<TabAtkins> proposed resolution: accept Rachel's text/direction
<TabAtkins> RESOLVED: accept Rachel's text/direction