Bug 1664446. Properly wait to make sure any potential scroll events get fired in several tests. r=kats

Doing rAF rAF flushApzRepaints is not enough to make sure that any potential scroll events are sent to content. The reason is that if the apz repaint request causes us to do scrolling on the main thread then the scrolling will be finished after flushApzRepaints, and the scroll event will be pending, but it's not sent until the next refresh driver tick. So we need to do at least one rAF after flushApzRepaints.

Differential Revision: https://phabricator.services.mozilla.com/D90035

editor/libeditor/tests/test_bug549262.html

@@ -38,18 +38,18 @@ function waitAndCheckNoScrollEvent(aWindow) {
   }
   aWindow.addEventListener("scroll", recordScroll, {capture: true});
   return new Promise(resolve => {aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(
-    () => { flushApzRepaints(
+    () => { flushApzRepaints(() => { aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(
       function() {
         aWindow.removeEventListener("scroll", recordScroll, {capture: true});
         is(gotScroll, false, "check that we didn't get a scroll");
         resolve();
-      }, aWindow
+      }); } ); }, aWindow
     ); }
   ); }); });
 }
 
 function waitToClearOutAnyPotentialScrolls(aWindow) {
-  return new Promise(resolve => {aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(() => { flushApzRepaints(resolve, aWindow); }); }); });
+  return new Promise(resolve => {aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(() => { flushApzRepaints(() => { aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(resolve); } ); }, aWindow); }); }); });
 }
 
 SimpleTest.waitForFocus(function() {

editor/libeditor/tests/test_bug915962.html

@@ -39,18 +39,18 @@ function waitAndCheckNoScrollEvent(aWindow) {
   }
   aWindow.addEventListener("scroll", recordScroll, {capture: true});
   return new Promise(resolve => {aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(
-    () => { flushApzRepaints(
+    () => { flushApzRepaints(() => { aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(
       function() {
         aWindow.removeEventListener("scroll", recordScroll, {capture: true});
         is(gotScroll, false, "check that we didn't get a scroll");
         resolve();
-      }, aWindow
+      }); } ); }, aWindow
     ); }
   ); }); });
 }
 
 function waitToClearOutAnyPotentialScrolls(aWindow) {
-  return new Promise(resolve => {aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(() => { flushApzRepaints(resolve, aWindow); }); }); });
+  return new Promise(resolve => {aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(() => { flushApzRepaints(() => { aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(resolve); } ); }, aWindow); }); }); });
 }
 
 SimpleTest.waitForFocus(function() {

editor/libeditor/tests/test_selection_move_commands.html

@@ -209,7 +209,7 @@ async function testRunner() {
       break;
     }
     await promise;
-    await new Promise(resolve => {win.requestAnimationFrame(() => { win.requestAnimationFrame(() => { flushApzRepaints(resolve, win); }); }); });
+    await new Promise(resolve => {win.requestAnimationFrame(() => { win.requestAnimationFrame(() => { flushApzRepaints(() => { win.requestAnimationFrame(() => { win.requestAnimationFrame(resolve); } ); }, win); }); }); });
   }
 }
 

layout/base/tests/test_bug1120705.html

@@ -52,7 +52,7 @@ function clickDownButton() {
 }
 
 function waitToClearOutAnyPotentialScrolls(aWindow) {
-  return new Promise(resolve => {aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(() => { flushApzRepaints(resolve, aWindow); }); }); });
+  return new Promise(resolve => {aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(() => { flushApzRepaints(() => { aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(resolve); } ); }, aWindow); }); }); });
 }
 
 function waitForScrollEvent(aWindow) {

layout/base/tests/test_scroll_per_page.html

@@ -63,9 +63,10 @@ async function doTests(aWindow) {
   }
 
   function waitToClearOutAnyPotentialScrolls() {
-    return new Promise(resolve => {aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(() => { flushApzRepaints(resolve, aWindow); }); }); });
+    return new Promise(resolve => {aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(() => { flushApzRepaints(() => { aWindow.requestAnimationFrame(() => { aWindow.requestAnimationFrame(resolve); } ); }, aWindow); }); }); });
   }
 
+
   async function doPageDown() {
     let waitForScrolling = waitForScrollEvent();
     if (kUseKeyboardEvent) {

layout/generic/test/test_bug633762.html

@@ -33,7 +33,8 @@ async function runTests() {
   win.focus();
 
   // clear out any potential scroll events so we can listen for the one we want without false positives
-  await new Promise(resolve => {window.requestAnimationFrame(() => { window.requestAnimationFrame(() => { flushApzRepaints(resolve, window); }); }); });
+  await new Promise(resolve => {window.requestAnimationFrame(() => { window.requestAnimationFrame(() => { flushApzRepaints(() => { window.requestAnimationFrame(() => { window.requestAnimationFrame(resolve); } ); }, window); }); }); });
+
   step2();
 }