[css-mixins-1][editorial] Update WPT paths and add missing WPTs

Author: kbabbitt

css-mixins-1/Overview.bs

@@ -137,9 +137,9 @@ Introduction {#intro}
 	</xmp>
 
 	<wpt>
-		function-in-media.html
-		local-inherit-substitution.html
-		local-var-substitution.html
+		functions/function-in-media.html
+		functions/local-inherit-substitution.html
+		functions/local-var-substitution.html
 	</wpt>
 
 <!-- Big Text: @function
@@ -222,9 +222,9 @@ and optionally a <dfn>default value</dfn>.
 </pre>
 
 <wpt>
-	at-function-parsing.html
-	dashed-function-named-arg.tentative.html
-	dashed-function-parsing.html
+	functions/at-function-parsing.html
+	functions/dashed-function-named-arg.tentative.html
+	functions/dashed-function-parsing.html
 </wpt>
 
 If a [=default value=] and a [=parameter type=] are both provided,
@@ -478,13 +478,13 @@ is the real element at the root of the [=calling context=] stack.
 </div>
 
 <wpt>
-	dashed-function-eval.html
-	dashed-function-standard-property.html
-	function-attr.html
-	function-shadow-animations.html
-	function-shadow-cache.html
-	function-shadow-container.html
-	function-shadow.html
+	functions/dashed-function-eval.html
+	functions/dashed-function-standard-property.html
+	functions/function-attr.html
+	functions/function-shadow-animations.html
+	functions/function-shadow-cache.html
+	functions/function-shadow-container.html
+	functions/function-shadow.html
 </wpt>
 
 <div class='example'>
@@ -643,9 +643,9 @@ with its [=function parameters=] overriding "inherited" custom properties of the
 </div>
 
 <wpt>
-	dashed-function-cycles.html
-	local-attr-substitution.html
-	local-if-substitution.html
+	functions/dashed-function-cycles.html
+	functions/local-attr-substitution.html
+	functions/local-if-substitution.html
 </wpt>
 
 <div algorithm>
@@ -802,12 +802,12 @@ when the condition is true,
 or acting as if nothing exists at that location otherwise.
 
 <wpt>
-	function-conditionals.html
-	function-container-dynamic.html
-	function-container-self.html
-	function-container-style.html
-	function-layer.html
-	function-media-dynamic.html
+	functions/function-conditionals.html
+	functions/function-container-dynamic.html
+	functions/function-container-self.html
+	functions/function-container-style.html
+	functions/function-layer.html
+	functions/function-media-dynamic.html
 </wpt>
 
 <div class='example'>
@@ -875,10 +875,10 @@ but rather than extending/upgrading [=custom properties=],
 making them reusable and customizable with arguments.
 
 <wpt>
-	mixin-basic.html
-	mixin-declarations.html
-	mixin-parsing.html
-	mixin-shadow-dom.html
+	mixins/mixin-basic.html
+	mixins/mixin-declarations.html
+	mixins/mixin-parsing.html
+	mixins/mixin-shadow-dom.html
 </wpt>
 
 <div class=example>
@@ -961,8 +961,9 @@ and that the parameter list and enclosing parentheses are optional.)
 </pre>
 
 <wpt>
-	mixin-media-query-invalidation-2.html
-	mixin-media-query-invalidation.html
+	mixins/mixin-media-query-invalidation-2.html
+	mixins/mixin-media-query-invalidation.html
+	mixins/mixin-parameters.html
 </wpt>
 
 If a [=default value=] and a [=parameter type=] are both provided,
@@ -1016,7 +1017,9 @@ Unknown properties and rules are invalid and ignored,
 but do not make the ''@mixin'' rule itself invalid.
 
 <wpt>
-	mixin-layers.html
+	mixins/mixin-conditionals.html
+	mixins/mixin-layers.html
+	mixins/mixin-locals.html
 </wpt>
 
 <h3 id=result-rule at-rule lt="@result" export>
@@ -1359,9 +1362,9 @@ The syntax of a ''@contents'' at-rule is:
 </pre>
 
 <wpt>
-	contents-nested-declarations-fallback.html
-	contents-nested-declarations.html
-	contents-rule.html
+	mixins/contents-nested-declarations-fallback.html
+	mixins/contents-nested-declarations.html
+	mixins/contents-rule.html
 </wpt>
 
 That is, it is either an <em>empty</em> statement ended immediately by a semicolon,
@@ -1573,10 +1576,10 @@ as a [=nested declarations rule=]
 via the ''@apply'' rule.
 
 <wpt>
-	apply-nested-declarations.html
-	mixin-cross-stylesheet.html
-	mixin-from-import-with-media-queries.html
-	mixin-from-import.html
+	mixins/apply-nested-declarations.html
+	mixins/mixin-cross-stylesheet.html
+	mixins/mixin-from-import-with-media-queries.html
+	mixins/mixin-from-import.html
 </wpt>
 
 <!-- Big Text: @apply
@@ -1604,8 +1607,8 @@ Its grammar is:
 </pre>
 
 <wpt>
-	apply-top-level.html
-	apply-within-mixin.html
+	mixins/apply-top-level.html
+	mixins/apply-within-mixin.html
 </wpt>
 
 <div class=example>
@@ -2253,8 +2256,8 @@ CSSOM {#cssom}
 Issue: TODO Supply the OM for ''@mixin''/etc.
 
 <wpt>
-	at-function-cssom.html
-	function-invalidation.html
+	functions/at-function-cssom.html
+	functions/function-invalidation.html
 </wpt>
 
 The {{CSSFunctionRule}} Interface {#the-function-interface}