[SoftNavigations] Fix up ViewTransition test

Bug: 1405448
Change-Id: I034ca223da8a55be0230195e648e48c32341878a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4369840
Commit-Queue: Yoav Weiss <yoavweiss@chromium.org>
Reviewed-by: Khushal Sagar <khushalsagar@chromium.org>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1122098}

third_party/blink/web_tests/VirtualTestSuites

@@ -1192,7 +1192,8 @@
     "bases": ["external/wpt/css/css-view-transitions",
               "wpt_internal/view-transition",
               "view-transition",
-              "inspector-protocol/css/css-get-styles-for-view-transition.js"],
+              "inspector-protocol/css/css-get-styles-for-view-transition.js",
+              "external/wpt/soft-navigation-heuristics/navigation-api-view-transition.tentative.html"],
     "exclusive_tests": "ALL",
     "args": ["--enable-threaded-compositing"],
     "expires": "Jul 1, 2023"

third_party/blink/web_tests/external/wpt/soft-navigation-heuristics/navigation-api-view-transition.tentative.html

@@ -26,17 +26,19 @@
         timestamps[counter]["eventStart"] = performance.now();
         e.intercept({
           async handler() {
-            await document.startViewTransition(async () => {
+            const lcp_promise = new Promise(resolve => {
+             (new PerformanceObserver(list => resolve())).observe(
+               {type: 'largest-contentful-paint',
+                includeSoftNavigationObservations: true});
+             });
+            const transition = document.startViewTransition(async () => {
               const main = document.getElementById('main');
               main.innerHTML = '<img id="image" src="/images/blue.png?' +
                 Math.random() + '">';
               const img = document.getElementById("image");
-              await new Promise(resolve => {
-               (new PerformanceObserver(list => resolve())).observe(
-                 {type: 'largest-contentful-paint',
-                  includeSoftNavigationObservations: true});
-               });
             });
+            await transition.updateCallbackDone;
+            await lcp_promise;
           }
         });
       };

third_party/blink/web_tests/external/wpt/soft-navigation-heuristics/resources/soft-navigation-helper.js

@@ -49,12 +49,17 @@ const testNavigationApi = (testName, navigateEventHandler, link) => {
   promise_test(async t => {
     const preClickLcp = await getLcpEntries();
     navigation.addEventListener('navigate', navigateEventHandler);
+    const navigated = new Promise(resolve => {
+      navigation.addEventListener('navigatesuccess', resolve);
+      navigation.addEventListener('navigateerror', resolve);
+    });
     click(link);
     await new Promise(resolve => {
       (new PerformanceObserver(() => resolve())).observe({
         type: 'soft-navigation'
       });
     });
+    await navigated;
     assert_equals(document.softNavigations, 1, 'Soft Navigation detected');
     await validateSoftNavigationEntry(1, () => {}, 'foobar.html');