Bug 1575417 [wpt PR 18574] - Update wpt metadata, a=testonly

wpt-pr: 18574
wpt-type: metadata

UltraBlame original commit: 82eed622a6a87ca1f9cc3a8c4e0b575141046dc8

Author: marco-c

testing/web-platform/meta/css/css-backgrounds/background-position-negative-percentage-comparison.html.ini

@@ -0,0 +1,2 @@
+[background-position-negative-percentage-comparison.html]
+  expected: FAIL

testing/web-platform/meta/css/css-values/minmax-percentage-computed.html.ini

@@ -0,0 +1,40 @@
+[minmax-percentage-computed.html]
+  [Property margin-left value 'calc(min(10%, 20%) / 2)' computes to '20px']
+    expected: FAIL
+
+  [Property margin-left value 'calc(max(10%, 20%) * 2)' computes to '160px']
+    expected: FAIL
+
+  [Property margin-left value 'min(1%)' computes to '4px']
+    expected: FAIL
+
+  [Property margin-left value 'max(1%)' computes to '4px']
+    expected: FAIL
+
+  [Property margin-left value 'min(20%, max(10%, 15%))' computes to '60px']
+    expected: FAIL
+
+  [Property margin-left value 'calc(min(10%, 20%) * 2)' computes to '80px']
+    expected: FAIL
+
+  [Property margin-left value 'calc(max(10%, 20%) - 5%)' computes to '60px']
+    expected: FAIL
+
+  [Property margin-left value 'calc(max(10%, 20%) / 2)' computes to '40px']
+    expected: FAIL
+
+  [Property margin-left value 'calc(min(10%, 20%) - 5%)' computes to '20px']
+    expected: FAIL
+
+  [Property margin-left value 'calc(min(10%, 20%) + 5%)' computes to '60px']
+    expected: FAIL
+
+  [Property margin-left value 'calc(min(10%, 20%) + max(10%, 5%))' computes to '80px']
+    expected: FAIL
+
+  [Property margin-left value 'max(10%, min(20%, 15%))' computes to '60px']
+    expected: FAIL
+
+  [Property margin-left value 'calc(max(10%, 20%) + 5%)' computes to '100px']
+    expected: FAIL
+