[css-flexbox] Simplify intrinsic aspect ratio handling of main size, clarify definite sizing in stretch cases.

Author: fantasai

css-flexbox/Overview.html

@@ -1993,11 +1993,14 @@ <h2 class="heading settled heading" data-level=9 id=layout-algorithm><span class
 		i.e. is a <var>&lt;length&gt;</var>,
 		a size of the initial containing block,
 		or a <var>&lt;percentage&gt;</var> that is resolved against a definite size.
-		If a <a data-link-type=dfn href=#single-line title=single-line>single-line</a> <a data-link-type=dfn href=#flex-container title="flex container">flex container</a> has a definite cross size,
-		any <a data-link-type=dfn href=#flex-item title="flex items">flex items</a> with <a class=css data-link-type=propdesc href=#propdef-align-self title=align-self>align-self: stretch</a> must also be treated as having a definite cross size
-		(since its size is determined from the size of the <a data-link-type=dfn href=#flex-container title="flex container">flex container</a>).
 		An <dfn data-dfn-type=dfn data-noexport="" id=indefinite title="indefinite|indefinite size">indefinite size<a class=self-link href=#indefinite></a></dfn> is one that is not <a data-link-type=dfn href=#definite title=definite>definite</a>.
 
+	<p>
+		As a special case for handling stretched <a data-link-type=dfn href=#flex-item title="flex items">flex items</a>,
+		if a <a data-link-type=dfn href=#single-line title=single-line>single-line</a> <a data-link-type=dfn href=#flex-container title="flex container">flex container</a> has a definite cross size,
+		any <a data-link-type=dfn href=#flex-item title="flex items">flex items</a> with <a class=css data-link-type=propdesc href=#propdef-align-self title=align-self>align-self: stretch</a> must also be treated as having a definite cross size
+		of the flex container’s inner cross size (clamped to the <a data-link-type=dfn href=#flex-item title="flex item">flex item</a>’s min and max <a data-link-type=dfn href=#cross-size title="cross size">cross size</a>).
+
 	<p>
 		The following sections define the algorithm for laying out a flex container and its contents.
 
@@ -2057,15 +2060,13 @@ <h3 class="heading settled heading" data-level=9.2 id=line-sizing><span class=se
 					The <a data-link-type=dfn href=#flex-base-size title="flex base size">flex base size</a> is the item’s resulting main size.
 
 				<li>
-					If the flex item ...
+					If the flex item has ..
 					<ul>
-						<li>has an intrinsic aspect ratio
-						<li>has <a class=css data-link-type=propdesc href=#propdef-align-self title=align-self>align-self: stretch</a>,
-						<li>has a <a data-link-type=dfn href=#flex-basis title="flex basis">flex basis</a> and cross size both <a class=css-code data-link-for=width data-link-type=value title=auto>auto</a>
+						<li>an intrinsic aspect ratio
+						<li>a <a data-link-type=dfn href=#flex-basis title="flex basis">flex basis</a> of <a class=css-code data-link-for=width data-link-type=value title=auto>auto</a>
+						<li>a definite <a data-link-type=dfn href=#cross-size title="cross size">cross size</a>
 					</ul>
-					and the flex container is <a data-link-type=dfn href=#single-line title=single-line>single-line</a> and has a <a data-link-type=dfn href=#definite title=definite>definite</a> cross size,
-					the <a data-link-type=dfn href=#flex-base-size title="flex base size">flex base size</a> is computed from the flex container’s inner cross size
-					(clamped to the <a data-link-type=dfn href=#flex-item title="flex item">flex item</a>’s min and max <a data-link-type=dfn href=#cross-size title="cross size">cross size</a>)
+					then the <a data-link-type=dfn href=#flex-base-size title="flex base size">flex base size</a> is calculated from its <a data-link-type=dfn href=#cross-size title="cross size">cross size</a>
 					and the <a data-link-type=dfn href=#flex-item title="flex item">flex item</a>’s intrinsic aspect ratio.
 
 					<p class=issue id=issue-8a5126c8><a class=self-link href=#issue-8a5126c8></a>

css-flexbox/Overview.src.html

@@ -1976,11 +1976,14 @@ <h2 id='layout-algorithm'>
 		i.e. is a <var>&lt;length></var>,
 		a size of the initial containing block,
 		or a <var>&lt;percentage></var> that is resolved against a definite size.
-		If a <i>single-line</i> <i>flex container</i> has a definite cross size,
-		any <i>flex items</i> with ''align-self: stretch'' must also be treated as having a definite cross size
-		(since its size is determined from the size of the <i>flex container</i>).
 		An <dfn title="indefinite|indefinite size">indefinite size</dfn> is one that is not <i>definite</i>.
 
+	<p>
+		As a special case for handling stretched <i>flex items</i>,
+		if a <i>single-line</i> <i>flex container</i> has a definite cross size,
+		any <i>flex items</i> with ''align-self: stretch'' must also be treated as having a definite cross size
+		of the flex container's inner cross size (clamped to the <i>flex item</i>&rsquo;s min and max <i>cross size</i>).
+
 	<p>
 		The following sections define the algorithm for laying out a flex container and its contents.
 
@@ -2044,15 +2047,13 @@ <h3 id='line-sizing'>
 					The <i>flex base size</i> is the item's resulting main size.
 
 				<li>
-					If the flex item ...
+					If the flex item has ..
 					<ul>
-						<li>has an intrinsic aspect ratio
-						<li>has ''align-self: stretch'',
-						<li>has a <a>flex basis</a> and cross size both <a value for=width>auto</a>
+						<li>an intrinsic aspect ratio
+						<li>a <a>flex basis</a> of <a value for=width>auto</a>
+						<li>a definite <i>cross size</i>
 					</ul>
-					and the flex container is <i>single-line</i> and has a <i>definite</i> cross size,
-					the <i>flex base size</i> is computed from the flex container's inner cross size
-					(clamped to the <i>flex item</i>&rsquo;s min and max <i>cross size</i>)
+					then the <i>flex base size</i> is calculated from its <i>cross size</i>
 					and the <i>flex item</i>&rsquo;s intrinsic aspect ratio.
 
 					<p class='issue'>