Removes the mandatory mediation requirement for digital credentials API

digital-credentials/allow-attribute-with-create.https.html

@@ -107,7 +107,6 @@
                                 // Results in TypeError when allowed, NotAllowedError when disallowed
                                 requests: [],
                             },
-                            mediation: "required",
                         };
                         const { data } = await new Promise((resolve) => {
                             window.addEventListener("message", resolve, {

digital-credentials/allow-attribute-with-get.https.html

@@ -108,7 +108,6 @@
                                 // NotAllowedError when disallowed
                                 requests: [],
                             },
-                            mediation: "required",
                         };
                         await test_driver.bless("User activation");
                         const { data } = await new Promise((resolve) => {

digital-credentials/create.tentative.https.html

@@ -17,7 +17,6 @@
 
   const iframeSameOrigin = document.querySelector("iframe#same-origin");
   const iframeCrossOrigin = document.querySelector("iframe#cross-origin");
-  const mediations = ["silent", "optional", "conditional", "required"];
 
   promise_setup(async () => {
     const hostInfo = get_host_info();
@@ -209,6 +208,8 @@
   }, "navigator.credentials.create() promise is rejected if abort controller is aborted after call to create() in cross-origin iframe.");
 
   promise_test(async (t) => {
+    /** @type sequence<CredentialMediationRequirement> */
+    const mediations = ["silent", "optional", "conditional", "required"];
     const abortController = new AbortController();
     const { signal } = abortController;
     abortController.abort();
@@ -219,16 +220,7 @@
       });
       await promise_rejects_dom(t, "AbortError", requestPromise);
     }
-  }, "Adding mediations together with abort signal respects the abort signal.");
-
-  promise_test(async (t) => {
-    /** @type sequence<CredentialMediationRequirement> */
-    const disallowedMediations = [ "conditional", "optional", "silent"];
-    for (const mediation of disallowedMediations) {
-      const options = makeCreateOptions("default", mediation);
-      await promise_rejects_js(t, TypeError, navigator.credentials.create(options));
-    }
-  }, "Mediation is required to create a DigitalCredential.");
+  }, "Mediation is implicitly required and hence ignored. Request is aborted regardless.");
 
   promise_test(async (t) => {
     await promise_rejects_js(

digital-credentials/get.tentative.https.html

@@ -233,16 +233,18 @@
 
   promise_test(async (t) => {
     /** @type sequence<CredentialMediationRequirement> */
-    const disallowedMediations = ["conditional", "optional", "silent"];
-    for (const mediation of disallowedMediations) {
-      const options = makeGetOptions("default", mediation);
-      await promise_rejects_js(
-        t,
-        TypeError,
-        navigator.credentials.get(options)
-      );
+    const mediations = ["silent", "optional", "conditional", "required"];
+    const abortController = new AbortController();
+    const { signal } = abortController;
+    abortController.abort();
+    for (const mediation of mediations) {
+      const requestPromise = navigator.credentials.get({
+        mediation,
+        signal,
+      });
+      await promise_rejects_dom(t, "AbortError", requestPromise);
     }
-  }, "Mediation is required to get a DigitalCredential.");
+  }, "Mediation is implicitly required and hence ignored. Request is aborted regardless.");
 
 promise_test(async t => {
   const throwingValues = [