Rename metadata directories

This renames:
 - `tests/wpt/metadata` → `tests/wpt/meta-legacy-layout`
 - `tests/wpt/metadata-layout-2020` → `tests/wpt/meta`
 - `tests/wpt/mozilla/meta` → `tests/wpt/mozilla/meta-legacy-layout`
 - `tests/wpt/mozilla/meta-layout-2020` → `tests/wpt/mozilla/meta`

tests/wpt/meta/css/css-transforms/animation/transform-interpolation-006.html.ini

@@ -0,0 +1,73 @@
+[transform-interpolation-006.html]
+  [Web Animations: property <transform> from neutral to [translate(20px)\] at (0.75) should be [translate(17.5px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [initial\] to [translate(20px)\] at (0.75) should be [translate(15px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [unset\] to [translate(20px)\] at (1) should be [translate(20px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [inherit\] to [translate(20px)\] at (-1) should be [translate(40px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [unset\] to [translate(20px)\] at (0.75) should be [translate(15px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [unset\] to [translate(20px)\] at (0) should be [translate(0px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from neutral to [translate(20px)\] at (2) should be [translate(30px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from neutral to [translate(20px)\] at (0.25) should be [translate(12.5px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [unset\] to [translate(20px)\] at (-1) should be [translate(-20px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [initial\] to [translate(20px)\] at (1) should be [translate(20px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [inherit\] to [translate(20px)\] at (2) should be [translate(10px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [inherit\] to [translate(20px)\] at (0.25) should be [translate(27.5px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [inherit\] to [translate(20px)\] at (0.75) should be [translate(22.5px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [unset\] to [translate(20px)\] at (2) should be [translate(40px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from neutral to [translate(20px)\] at (0) should be [translate(10px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [initial\] to [translate(20px)\] at (0) should be [translate(0px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [inherit\] to [translate(20px)\] at (0) should be [translate(30px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [inherit\] to [translate(20px)\] at (1) should be [translate(20px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [unset\] to [translate(20px)\] at (0.25) should be [translate(5px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from neutral to [translate(20px)\] at (-1) should be [translate(0px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [initial\] to [translate(20px)\] at (0.25) should be [translate(5px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from neutral to [translate(20px)\] at (1) should be [translate(20px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [initial\] to [translate(20px)\] at (-1) should be [translate(-20px)\]]
+    expected: FAIL
+
+  [Web Animations: property <transform> from [initial\] to [translate(20px)\] at (2) should be [translate(40px)\]]
+    expected: FAIL
+