Fix ref image for border-radius-dynamic-from-no-radius

Drawing a 100px x 100px div with border radius 50px is not the same as
with border radius calc(100% - 1px) = 99px.

R=foolip@chromium.org
BUG=968430

Change-Id: I953c26b72d55d930cdbbcfa969f38b892e3151f7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1639566
Auto-Submit: Stephen Chenney <schenney@chromium.org>
Commit-Queue: Philip Jägenstedt <foolip@chromium.org>
Reviewed-by: Philip Jägenstedt <foolip@chromium.org>
Cr-Commit-Position: refs/heads/master@{#666247}

third_party/blink/web_tests/TestExpectations

@@ -2846,9 +2846,6 @@ crbug.com/626703 [ Win ] external/wpt/css/css-sizing/clone-intrinsic-size.html [
 crbug.com/626703 [ Linux ] external/wpt/infrastructure/testdriver/actions/actionsWithKeyPressed.html [ Timeout ]
 crbug.com/626703 [ Mac ] external/wpt/infrastructure/testdriver/actions/actionsWithKeyPressed.html [ Timeout ]
 crbug.com/626703 [ Win ] external/wpt/infrastructure/testdriver/actions/actionsWithKeyPressed.html [ Timeout ]
-crbug.com/626703 [ Linux ] external/wpt/css/css-backgrounds/border-radius-dynamic-from-no-radius.html [ Failure ]
-crbug.com/626703 [ Mac ] external/wpt/css/css-backgrounds/border-radius-dynamic-from-no-radius.html [ Failure ]
-crbug.com/626703 [ Win ] external/wpt/css/css-backgrounds/border-radius-dynamic-from-no-radius.html [ Failure ]
 crbug.com/626703 [ Retina ] external/wpt/html/browsers/the-window-object/apis-for-creating-and-navigating-browsing-contexts-by-name/open-features-tokenization-screenx-screeny.html [ Timeout ]
 crbug.com/626703 [ Mac10.12 ] external/wpt/media-source/mediasource-config-change-webm-av-framesize.html [ Timeout ]
 crbug.com/626703 [ Mac10.12 ] external/wpt/html/semantics/embedded-content/media-elements/track/track-element/track-cue-negative-duration.html [ Timeout ]

third_party/blink/web_tests/external/wpt/css/css-backgrounds/border-radius-dynamic-from-no-radius-ref.html

@@ -11,7 +11,7 @@
     width: 100%;
     height: 100%;
     background: green;
-    border-radius: 50px;
+    border-radius: 99px;
   }
 </style>
 <p>Should be a green circle below</p>