Remove testRunner.display() from most compositing/ tests

LayoutTests/resources/run-after-display.js

Index: LayoutTests/resources/run-after-display.js
diff --git a/LayoutTests/resources/run-after-display.js b/LayoutTests/resources/run-after-display.js
new file mode 100644
index 0000000000000000000000000000000000000000..c42de0fa4429b14fb6bc2605a6222e445fd95ea7
--- /dev/null
+++ b/LayoutTests/resources/run-after-display.js
@@ -0,0 +1,8 @@
+function runAfterDisplay(callback) {
+    window.requestAnimationFrame(function() {
+        // At this point, only the animate has happened, but no compositing
+        // or layout.  Use a timeout for the callback so that notifyDone
+        // can be called inside of it.
+        window.setTimeout(callback, 0);
+    });
+}