[macOS] Fix SuspendServiceWorkerProcessBasedOnClientProcessesWithoutS…

…eparateServiceWorkerProcess test when RunningBoard is enabled.

https://bugs.webkit.org/show_bug.cgi?id=247894
rdar://102320977

Reviewed by Darin Adler and Timothy Hatcher.

This test assumes that all webcontent processes associated with the
service worker have a suspended assertion. However, we currently 'leak'
a foreground assertion on every webcontent process by default when
we build with RunningBoard enabled. We should manually take a suspended
assertion on web content processes associated with this service worker
instead of assuming they already have a suspended assertion.

* Tools/TestWebKitAPI/Tests/WebKitCocoa/ServiceWorkerBasic.mm:

Canonical link: https://commits.webkit.org/257141@main

Tools/TestWebKitAPI/Tests/WebKitCocoa/ServiceWorkerBasic.mm

@@ -1753,6 +1753,9 @@ void testSuspendServiceWorkerProcessBasedOnClientProcesses(UseSeparateServiceWor
 
     auto webViewToUpdate = useSeparateServiceWorkerProcess == UseSeparateServiceWorkerProcess::Yes ? webView : webView2;
 
+    if (useSeparateServiceWorkerProcess == UseSeparateServiceWorkerProcess::Yes)
+        [webView2 _setThrottleStateForTesting:0];
+
     [webViewToUpdate _setThrottleStateForTesting:1];
     EXPECT_TRUE(waitUntilEvaluatesToTrue([&] {
         return ![webViewToUpdate _hasServiceWorkerForegroundActivityForTesting] && [webViewToUpdate _hasServiceWorkerBackgroundActivityForTesting];