Bug 1565010 - Fix intermittent on browser_webconsole_warn_about_replaced_api.js .r=Honza.

Log the console replaced message only after the current batch of messages are consumed.
We also enable the timestamp in the test, so in case of failure we can diagnose
what's going on better.

Differential Revision: https://phabricator.services.mozilla.com/D72121

Author: nchevobbe

devtools/client/webconsole/test/browser/browser_webconsole_warn_about_replaced_api.js

@@ -9,9 +9,8 @@ const TEST_URI_NOT_REPLACED =
   "data:text/html;charset=utf8,<script>console.log('foo')</script>";
 
 add_task(async function() {
-  await SpecialPowers.pushPrefEnv({
-    set: [["devtools.webconsole.persistlog", true]],
-  });
+  await pushPref("devtools.webconsole.timestampMessages", true);
+  await pushPref("devtools.webconsole.persistlog", true);
 
   let hud = await openNewTabAndConsole(TEST_URI_NOT_REPLACED);
 

devtools/client/webconsole/webconsole-ui.js

@@ -589,13 +589,14 @@ class WebConsoleUI {
    *        Notification packet received from the server.
    */
   async handleTabNavigated(packet) {
+    // Wait for completion of any async dispatch before notifying that the console
+    // is fully updated after a page reload
+    await this.wrapper.waitAsyncDispatches();
+
     if (!packet.nativeConsoleAPI) {
       this.logWarningAboutReplacedAPI();
     }
 
-    // Wait for completion of any async dispatch before notifying that the console
-    // is fully updated after a page reload
-    await this.wrapper.waitAsyncDispatches();
     this.emit("reloaded");
   }