Prerender WPT: add navigateExpectingNoPrerenderingActivation() helper (#52966)

This more clearly communicates the intent of these tests, and is a good
counterpart to navigateExpectingPrerenderingActivation().

Also fix one more missing await in these tests.

Bug: 40273170
Change-Id: I924a92534a6d139ef515787ad875ce80b21b712c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6620151
Reviewed-by: Hiroki Nakagawa <[email protected]>
Commit-Queue: Domenic Denicola <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1469158}

Co-authored-by: Domenic Denicola <[email protected]>

Author: chromium-wpt-export-bot

speculation-rules/prerender/cancel-prerendering-after-clear-site-data-cache-same-origin.tentative.https.html

@@ -48,8 +48,7 @@
   // Because Clear-Site-Data response header is sent, the existing prerender
   // is expected to be canceled.
   // And the navigation is expected to create another page instead of activation.
-  referrerRC.navigateTo(prerenderedRC.url);
-  assert_equals(await getActivationStart(prerenderedRC), 0);
+  await referrerRC.navigateExpectingNoPrerenderingActivation(prerenderedRC);
 }, "clear-site-data prerenderCache headers should prevent it from being activated");
 
 // Test that Clear-Site-Data header value "cache" clears prerender cache
@@ -83,8 +82,7 @@
   // Because Clear-Site-Data response header is sent, the existing prerender
   // is expected to be canceled.
   // And the navigation is expected to create another page instead of activation.
-  await referrerRC.navigateTo(prerenderedRC.url);
-  assert_equals(await getActivationStart(prerenderedRC), 0);
+  await referrerRC.navigateExpectingNoPrerenderingActivation(prerenderedRC);
 }, "clear-site-data cache headers should prevent it from being activated");
 </script>
 </body>

speculation-rules/prerender/credentialed-prerender-not-opt-in.https.html

@@ -21,7 +21,6 @@
 
   // Because the prerender doesn't use opt-in header, it is expected to be canceled.
   // And the navigation is expected to create another page instead of activation.
-  await referrerRC.navigateTo(prerenderedRC.url);
-  assert_equals(await getActivationStart(prerenderedRC), 0);
+  await referrerRC.navigateExpectingNoPrerenderingActivation(prerenderedRC);
 });
 </script>

speculation-rules/prerender/resources/utils.js

@@ -425,6 +425,40 @@ if (globalThis.PreloadingRemoteContextHelper) {
       );
     }
 
+    /**
+    * Navigates to the URL identified by `destinationRC`, but expects that the
+    * navigation does not cause a prerendering activation. (E.g., because the
+    * prerender was canceled by something in the test code.) If the navigation
+    * results in a prerendering activation, the returned promise will be
+    * rejected with a testharness.js AssertionError.
+    * @param {RemoteContextWrapper} destinationRC - The `RemoteContextWrapper`
+    *     pointing to the destination URL. Usually this is obtained by
+    *     prerendering (e.g., via `addPrerender()`), even though we are testing
+    *     that the prerendering does not activate.
+    * @param {(string) => Promise<undefined>} [navigateFn] - An optional
+    *     function to customize the navigation. It will be passed the URL of the
+    *     prerendered content, and will run as a script in this  (see
+    *     `RemoteContextWrapper.prototype.executeScript`). If not given,
+    *     navigation will be done via the `location.href` setter (see
+    *     `RemoteContextWrapper.prototype.navigateTo`).
+    * @returns {Promise<undefined>}
+    */
+    async navigateExpectingNoPrerenderingActivation(destinationRC, navigateFn) {
+      if (navigateFn === undefined) {
+        await this.navigateTo(destinationRC.url);
+      } else {
+        await this.navigate(navigateFn, [destinationRC.url]);
+      }
+
+      assert_equals(
+        await destinationRC.executeScript(() => {
+          return performance.getEntriesByType("navigation")[0].activationStart;
+        }),
+        0,
+        "The prerendered page must not be activated."
+      );
+    }
+
     /**
     * Starts prerendering a page with this `PreloadingRemoteContextWrapper` as the
     * referrer, using `<script type="speculationrules">`.
@@ -445,13 +479,6 @@ if (globalThis.PreloadingRemoteContextHelper) {
   };
 }
 
-async function getActivationStart(prerenderedRC) {
-  return await prerenderedRC.executeScript(() => {
-    const entry = performance.getEntriesByType("navigation")[0];
-    return entry.activationStart;
-  });
-}
-
 // Used by the opened window, to tell the main test runner to terminate a
 // failed test.
 function failTest(reason, uid) {