Move animations crash tests to subdirectory

third_party/WebKit/LayoutTests/animations/multiple-same-animations-asan-crash.html

-<script src="../resources/testharness.js"></script>
-<script src="../resources/testharnessreport.js"></script>
-<style>
-#target {
-  animation: test 1s, test 2s;
-}
-@keyframes test {
-  to { color: green; }
-}
-</style>
-<div id="target"></div>
-<script>
-var asyncHandle = async_test('Don\'t crash ASAN when updating style with an element that has two animations with the same keyframes name and different timings.');
-// Wait a frame to let the animations get created.
-requestAnimationFrame(function() {
-  // Force the next style recalc to be non-animation triggered.
-  target.style.color = 'blue';
-  requestAnimationFrame(function() {
-    asyncHandle.done();
-  });
-});
-</script>