Overcome antialias fuzziness in backgrounds tests with meta name="fuzzy" (#42646)

diff --git a/css/css-backgrounds/border-image-image-type-004.htm b/css/css-backgrounds/border-image-image-type-004.htm
index 1e6953e..222267c 100644
--- a/css/css-backgrounds/border-image-image-type-004.htm
+++ b/css/css-backgrounds/border-image-image-type-004.htm
@@ -7,6 +7,7 @@
         <link rel="match" href="reference/border-image-image-type-004-ref.html" />
         <meta name="flags" content="svg" />
         <meta name="assert" content="This test checks that the SVG image used for the border image is sliced into nine regions with inward offsets of: '40 30 20 10' vector coordinates from the top, right, bottom, and left edges of the image set by the 'border-image-slice' property." />
+        <meta name="fuzzy" content="maxDifference=0-1;totalPixels=0-100" />
         <style type="text/css">
             div
             {
diff --git a/css/css-backgrounds/border-image-image-type-005.htm b/css/css-backgrounds/border-image-image-type-005.htm
index 0503b5a..cb2668d 100644
--- a/css/css-backgrounds/border-image-image-type-005.htm
+++ b/css/css-backgrounds/border-image-image-type-005.htm
@@ -7,6 +7,7 @@
         <link rel="match" href="reference/border-image-image-type-004-ref.html" />
         <meta name="flags" content="svg" />
         <meta name="assert" content="This test checks that border image is sliced into nine regions with inward offsets of: '40% 30% 20% 10%' from the top, right, bottom, and left edges of the image. Percentages are relative to the size of the image: the width of the image for the horizontal offsets, the height for vertical offsets." />
+        <meta name="fuzzy" content="maxDifference=0-1;totalPixels=0-100" />
         <style type="text/css">
             div
             {
diff --git a/css/css-backgrounds/box-shadow-border-radius-001.html b/css/css-backgrounds/box-shadow-border-radius-001.html
index 6f81ca8..c309685 100644
--- a/css/css-backgrounds/box-shadow-border-radius-001.html
+++ b/css/css-backgrounds/box-shadow-border-radius-001.html
@@ -20,6 +20,8 @@
 
   -->
 
+  <meta name="fuzzy" content="maxDifference=0-42;totalPixels=0-4">
+
   <style>
   div
     {