[css-ruby] Rename ruby-merge: collapse to ruby-merge: merge

Closes #5004

Author: frivoal

css-ruby-1/Overview.bs

@@ -130,7 +130,7 @@ What is ruby?</h3>
 		the spacing between these Kanji characters is adjusted.
 		(This happens around the fourth Kanji character in the figure above.)
 		To avoid variable spacing between the Kanji characters in the example above
-		the hiragana annotations can be styled as a [=collapsed annotation=],
+		the hiragana annotations can be styled as a [=merged annotation=],
 		which will look more like the group-ruby example earlier.
 		However because the base-annotation [=pairings=] are recorded in the ruby structure,
 		if the text breaks across lines, the annotation characters will stay
@@ -561,7 +561,7 @@ Autohiding Base-identical Annotations</h3>
 		</div>
 	</div>
 
-	When the computed value of 'ruby-merge' is ''collapse'',
+	When the computed value of 'ruby-merge' is ''merge'',
 	the autohiding is disabled.
 	When the computed value of 'ruby-merge' is ''ruby-merge/auto'',
 	the user agent may decide whether to autohide or not,
@@ -1011,7 +1011,7 @@ Sharing Annotation Space: the 'ruby-merge' property</h3>
 
 	<pre class="propdef">
 	Name: ruby-merge
-	Value: separate | collapse | auto
+	Value: separate | merge | auto
 	Initial: separate
 	Applies to: ruby annotation containers
 	Inherited: yes
@@ -1022,7 +1022,7 @@ Sharing Annotation Space: the 'ruby-merge' property</h3>
 	This property controls how ruby annotation boxes should be rendered
 	when there are more than one in a ruby container box:
 	whether each pair should be kept separate,
-	the annotations should be <dfn lt="collapsed annotation">collapsed</dfn> and rendered as a group,
+	the annotations should be <dfn lt="merged annotation">merged</dfn> and rendered as a group,
 	or the separation should be determined based on the space available.
 
 	Possible values:
@@ -1040,7 +1040,7 @@ Sharing Annotation Space: the 'ruby-merge' property</h3>
 			</div>
 		</dd>
 
-		<dt><dfn>collapse</dfn>
+		<dt><dfn>merge</dfn>
 		<dd>
 			All [=ruby annotation boxes=] within the same [=ruby segment=] on the same line are concatenated,
 			and laid out as if their contents belonged to a single [=ruby annotation box=]
@@ -1052,7 +1052,7 @@ Sharing Annotation Space: the 'ruby-merge' property</h3>
 				The following two markups render the same both characters fit on one line:
 				<pre highlight=html>&lt;ruby&gt;無常&lt;rt&gt;むじょう&lt;/ruby&gt;</pre>
 				and:
-				<pre highlight=html>&lt;ruby style="ruby-merge:collapse"&gt;&lt;rb&gt;無&lt;rb&gt;常&lt;rt&gt;む&lt;rt&gt;じょう&lt;/ruby&gt;</pre>
+				<pre highlight=html>&lt;ruby style="ruby-merge:merge"&gt;&lt;rb&gt;無&lt;rb&gt;常&lt;rt&gt;む&lt;rt&gt;じょう&lt;/ruby&gt;</pre>
 				However, the second one renders the same as ''ruby-position: separate''
 				when the two bases are split across lines.
 			</div>
@@ -1074,7 +1074,7 @@ Sharing Annotation Space: the 'ruby-merge' property</h3>
 					Another, more simplified algorithm of “jukugo ruby” is
 					to render as ''separate'' if all ruby annotation boxes fit
 					within the advances of their corresponding base boxes,
-					and render as ''collapse'' otherwise.
+					and render as ''merge'' otherwise.
 				</div>
 		</dd>
 	</dl>
@@ -1671,7 +1671,7 @@ Changes since the 5 August 2014 WD</h3>
 		<li>Add back ''ruby-overhang: auto | none'' for basic control over ruby overhang behavior.
 		<li>Harmonize inlinification with the <a href="https://www.w3.org/TR/css-display-3/">CSS Display Module</a>.
 		<li>Allow UA to shift ruby/emphasis marks if they conflict with underlines/overlines.
-		<li>Disable auto-hiding when the computed value of 'ruby-merge' is ''collapse''.
+		<li>Disable auto-hiding when the computed value of 'ruby-merge' is <code>collapse</code>.
 		<li>Tweak the <a href="#default-stylesheet">default style sheet</a>.
 		<li>Add section defining interaction with <a href="#ruby-text-decoration">text decoration</a>.
 		<li>Defer the <css>right</css> and <css>left</css> values of 'ruby-position' to the next level.