Remove Sky tests that we don't intend to port to the new world

sky/tests/lowlevel/layers.sky

Index: sky/tests/lowlevel/layers.sky
diff --git a/sky/tests/lowlevel/layers.sky b/sky/tests/lowlevel/layers.sky
deleted file mode 100644
index f15ff018daea1f61aedae39ce56bd2c25eed5acf..0000000000000000000000000000000000000000
--- a/sky/tests/lowlevel/layers.sky
+++ /dev/null
@@ -1,80 +0,0 @@
-<sky>
-
-<import src="../resources/run-after-display.sky" />
-<style>
-  sky {
-    padding: 10px;
-  }
-  div {
-    width: 50px;
-    height: 50px;
-    white-space: nowrap;
-  }
-</style>
-Transforms
-<div style="transform: translate3d(10px, 10px, 0); background-color: pink;">
-  One
-  <div style="transform: translate3d(10px, 10px, 0); background-color: salmon;">
-    Two
-    <div style="transform: translate3d(10px, 10px, 0); background-color: papayawhip;">
-      Three
-    </div>
-  </div>
-</div>
-
-<div style="position: absolute; top: 250px;">
-  Opacity
-  <div style="opacity: 0.8; background-color: pink; transform: translate3d(0, 0, 0)">
-    One
-    <div style="opacity: 0.7; position: absolute; left: 15px; top: 10px; background-color: salmon;">
-      Two
-      <div style="opacity: 0.6; position: absolute; left: 15px; top: 10px; background-color: papayawhip;">
-        Three
-        <div style="opacity: 0; transform: translate3d(0, 10px, 0); background-color: papayawhip;">
-          Clear
-        </div>
-      </div>
-    </div>
-  </div>
-</div>
-
-
-<div style="position: absolute; right: 50px;">
-  <div style="background-color: red;">
-    1
-  </div>
-  <div style="position: absolute; left: 40px; top: 40px; z-index: 2; background-color: pink;">
-    4
-  </div>
-  <div style="position: absolute; left: 20px; top: 20px; z-index: 0; background-color: salmon;">
-    2
-  </div>
-  <div style="position: absolute; left: 35px; top: 20px; z-index: 1; background-color: papayawhip;">
-    3
-  </div>
-  <div style="background-color: green;">
-    1
-  </div>
-  z-index
-</div>
-
-<div style="position: absolute; bottom: 50px;">
-  Clip-path
-  <div style="background-color: pink; -webkit-clip-path: circle(25px at 25px 25px);">
-    <div style="background-color: salmon; -webkit-clip-path: circle(25px at 35px 35px);">
-      <div style="background-color: papayawhip; -webkit-clip-path: circle(25px at 45px 45px);"></div>
-    </div>
-  </div>
-</div>
-
-<script>
-import "dart:sky.internals" as internals;
-
-void main() {
-  runAfterDisplay(() {
-    internals.notifyTestComplete("");
-  });
-}
-</script>
-
-</sky>