Bug 1595086 - also freeze the presshell when setActive(false) is called to stop requestAnimationFrames; r=smaug

also freeze the presshell when setActive(false) is called to stop requestAnimationFrames

Differential Revision: https://phabricator.services.mozilla.com/D55343

--HG--
extra : moz-landing-system : lando

mobile/android/chrome/geckoview/GeckoViewContentChild.js

@@ -263,9 +263,11 @@ class GeckoViewContentChild extends GeckoViewChildModule {
       case "GeckoView:SetActive":
         if (content) {
           if (!aMsg.data.active) {
+            docShell.contentViewer.pausePainting();
             content.windowUtils.suspendTimeouts();
             this.timeoutsSuspended = true;
           } else if (this.timeoutsSuspended) {
+            docShell.contentViewer.resumePainting();
             content.windowUtils.resumeTimeouts();
             this.timeoutsSuspended = false;
           }