Fix assert message in subpixel-perspective-backface-hidden.html

Change-Id: I783825bb9362df3c1a43f10ac8666f69332bd774
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2238106
Commit-Queue: Manuel Rego <rego@igalia.com>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#776572}

third_party/blink/web_tests/external/wpt/css/css-transforms/subpixel-perspective-backface-hidden.html

@@ -2,7 +2,7 @@
 <link ref="help" href="https://drafts.csswg.org/css-transforms-2/#perspective-property">
 <link rel="help" href="https://drafts.csswg.org/css-transforms-2/#backface-visibility-property">
 <link rel="match" href="subpixel-perspective-backface-hidden-ref.html">
-<meta name="assert" content="Subpixel-positioned contents should not renderred the same regardless of perspective and backface-visibility:hidden">
+<meta name="assert" content="Subpixel-positioned contents should be rendered the same regardless of perspective and backface-visibility:hidden">
 <div style="padding: 0.4px 0.6px">
   <div style="perspective: 1000px; backface-visibility: hidden">
     <div style="width: 100px; height: 100px;