[FedCM] Ignore unexpected messages

Webdriver internally uses testdriver-complete messages.
We should ignore them when waiting for messages from our
iframe.

This fixes the three changed tests on wpt.fyi.

Bug: 331237776
Change-Id: Id274b724d5974b646f1ca4c389820befc9072109
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5721452
Reviewed-by: Nicolás Peña <[email protected]>
Commit-Queue: Christian Biesinger <[email protected]>
Auto-Submit: Christian Biesinger <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1330510}

Author: cbiesinger

fedcm/fedcm-authz/fedcm-userinfo-after-resolve.https.html

@@ -21,7 +21,11 @@
     iframe.src = iframeUrl;
     iframe.allow = "identity-credentials-get";
     document.body.appendChild(iframe);
-    const message = await messageWatcher.wait_for("message");
+    let message = null;
+    // Ignore internal "testdriver-complete" messages.
+    do {
+        message = await messageWatcher.wait_for("message");
+    } while (!("result" in message.data));
     return message.data;
 }
 

fedcm/fedcm-pending-userinfo.https.html

@@ -20,7 +20,11 @@
     iframe.src = iframeUrl;
     iframe.allow = "identity-credentials-get";
     document.body.appendChild(iframe);
-    const message = await messageWatcher.wait_for("message");
+    let message = null;
+    // Ignore internal "testdriver-complete" messages.
+    do {
+        message = await messageWatcher.wait_for("message");
+    } while (typeof message.data !== "string");
     return message.data;
 }
 

fedcm/fedcm-userinfo.https.html

@@ -20,7 +20,11 @@
     iframe.src = iframeUrl;
     iframe.allow = "identity-credentials-get";
     document.body.appendChild(iframe);
-    const message = await messageWatcher.wait_for("message");
+    let message = null;
+    // Ignore internal "testdriver-complete" messages.
+    do {
+        message = await messageWatcher.wait_for("message");
+    } while (!("result" in message.data));
     return message.data;
 }