Auto merge of #12449 - servo:jdm-patch-1, r=Ms2ger

Add a manual test for measuring DOM binding performance

This is the test harness I've been using for profiling and measuring in #12354.

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1 files changed, 36 insertions, 0 deletions

diff --git a/tests/html/bindings_perf.html b/tests/html/bindings_perf.html
new file mode 100644
index 00000000000..d50cf940c32
--- /dev/null
+++ b/tests/html/bindings_perf.html
@@ -0,0 +1,36 @@
+<button onclick="void_method()">measure void method</button>
+<button onclick="int_getter()">measure int getter</button>
+<button onclick="firstChild_getter()">measure firstChild getter</button>
+<script>
+var t = 'TestBinding' in window ? (new TestBinding()) : (new TextEncoder());
+function void_method() {
+  var start = new Date();
+  var count = 1000000;
+  for (var i = 0; i < count; i++) {
+    var a = t.receiveVoid();
+  }
+  var stop = new Date();
+  console.log('void method: ' + ((stop - start) / count * 1e6) + 'ns');
+}
+
+function int_getter() {
+  var start = new Date();
+  var count = 1000000;
+  for (var i = 0; i < count; i++) {
+    var a = t.longAttribute;
+  }
+  var stop = new Date();
+  console.log('int getter: ' + ((stop - start) / count * 1e6) + 'ns');
+}
+
+function firstChild_getter() {
+  var n = document.documentElement;
+  var start = new Date();
+  var count = 100000000;
+  for (var i = 0; i < count; i++) {
+    var a = n.firstChild;
+  }
+  var stop = new Date();
+  console.log('firstChild getter: ' + ((stop - start) / count * 1e6) + 'ns');
+}
+</script>