Restore --unsafely-treat-insecure-origin-as-secure flag for Blazor WASM Lighthouse scenario (#2157)

* Restore --unsafely-treat-insecure-origin-as-secure flag for Blazor WASM Lighthouse scenario

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Also accept cached (fromCache) responses in WASM caching check

The WASM caching enforcement check previously only accepted HTTP 304
(Not Modified) as proof that a .wasm resource was cached. However,
browsers may serve cached resources with HTTP 200 from disk/memory
cache without making a network round-trip at all. Puppeteer exposes
this via response.fromCache(). Both cases indicate the resource was
properly cached after the first page load, so both should be accepted.

Without this fix, the 'Second page load' step fails with:
  Unexpected uncached wasm resource '...System.Runtime.InteropServices.JavaScript.*.wasm'
even though the resource is served from the browser cache.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: ilonatommy

src/BenchmarksApps/Lighthouse/src/blazor-scenario.js

@@ -24,7 +24,13 @@ logReadyStateText(); // Required by the Crank job
 
 const browser = await puppeteer.launch({
   headless: headless === 'true',
-  args: ['--no-sandbox']
+  args: [
+    '--no-sandbox',
+    // Treat the target URL as a secure origin so that crypto.subtle is available.
+    // This is needed because Blazor WASM requires crypto.subtle, which is only
+    // available in secure contexts (HTTPS or localhost).
+    `--unsafely-treat-insecure-origin-as-secure=${targetBaseUrl}`,
+  ],
 });
 
 const pageUrl = `${targetBaseUrl}/counter`;
@@ -126,7 +132,8 @@ function throwOnFutureUncachedWasmDownloads(page) {
 
   page.on('requestfinished', request => {
     const url = request.url();
-    if (url.endsWith('.wasm') && request.response().status() !== 304) {
+    const response = request.response();
+    if (url.endsWith('.wasm') && response.status() !== 304 && !response.fromCache()) {
       throw new Error(`Unexpected uncached wasm resource '${url}'`);
     }
   });