[iframe] Switch the property to frame-sizing

This patch switches the responsive iframe CSS property from
`contain-intrinsic-block-size` to `frame-sizing`, as resolved
on Jan 27th[1].

Tests are also updated, with two exceptions:
* `responsive-iframe-logical.tentative.html` isn't meaningful
  that it is removed.
* The fallback sizing was postponed to resolve, and thus its
  test `responsive-iframe-fallback.tentative.html` is expected
  to fail.

All changes are under a runtime flag currently experimental.

[1] w3c/csswg-drafts#1771 (comment)

Bug: 418397278
Change-Id: If0f1db67a9690f9a58392b6a704d3dc405954cfd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7532195
Reviewed-by: Kent Tamura <[email protected]>
Auto-Submit: Koji Ishii <[email protected]>
Commit-Queue: Kent Tamura <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1576859}

Author: kojiishi

css/css-sizing/responsive-iframe/responsive-iframe-cross-origin.sub.tentative.html

@@ -5,8 +5,8 @@
 <link rel="match" href="responsive-iframe-ref.html">
 <style>
 iframe {
-    border: 1px solid black;
-    contain-intrinsic-size: from-element none;
+  border: 1px solid black;
+  frame-sizing: content-height;
 }
 </style>
 <iframe frameborder=0 src="http://{{hosts[alt][]}}:{{ports[http][0]}}/css/css-sizing/responsive-iframe/resources/iframe-contents.html">

css/css-sizing/responsive-iframe/responsive-iframe-dom-content-loaded.tentative.html

@@ -6,7 +6,7 @@
 <script src="/resources/testharnessreport.js"></script>
 <style>
 iframe {
-  contain-intrinsic-size: from-element none;
+  frame-sizing: content-height;
 }
 </style>
 <iframe id="target" frameborder=0 src="resources/iframe-contents-dom-content-loaded.html"></iframe>

css/css-sizing/responsive-iframe/responsive-iframe-icb.tentative.html

@@ -7,7 +7,7 @@
 <style>
 iframe {
   border: 1px solid black;
-  contain-intrinsic-size: from-element none;
+  frame-sizing: content-height;
 }
 </style>
 <iframe id="target" frameborder=0 src="resources/iframe-contents-icb.html"></iframe>

css/css-sizing/responsive-iframe/responsive-iframe-logical.tentative.html

@@ -5,8 +5,8 @@
 <link rel="match" href="responsive-iframe-unsized-ref.html">
 <style>
 iframe {
-    border: 1px solid black;
-    contain-intrinsic-size: from-element none;
+  border: 1px solid black;
+  frame-sizing: content-height;
 }
 </style>
 <iframe frameborder=0 scrolling=no src="resources/iframe-contents-unsized.html">

css/css-sizing/responsive-iframe/responsive-iframe-not-embedded-sized.tentative.html

@@ -6,7 +6,7 @@
 <style>
 iframe {
   border: 1px solid black;
-  contain-intrinsic-size: from-element none;
+  frame-sizing: content-height;
 }
 </style>
 <iframe frameborder=0 src="resources/iframe-contents-request-resize.html">

css/css-sizing/responsive-iframe/responsive-iframe-request-resize.tentative.html

@@ -5,8 +5,8 @@
 <link rel="match" href="responsive-iframe-ref.html">
 <style>
 iframe {
-    border: 1px solid black;
-    contain-intrinsic-size: from-element none;
+  border: 1px solid black;
+  frame-sizing: content-height;
 }
 </style>
 <iframe frameborder=0 src="resources/iframe-contents.html">