IndexedDB.IndexedDBPersistence is flakily failing

https://bugs.webkit.org/show_bug.cgi?id=274099
rdar://128014218

Reviewed by Alex Christensen.

The second message might arrive on the first wait, so instead of starting a second wait, the test should check whether
first message has arrived after first wait. This is what getNextMessage() does, and the test doesn't need to do explicit
wait.

* Tools/TestWebKitAPI/Tests/WebKitCocoa/IndexedDBPersistence.mm:
(TEST(IndexedDB, IndexedDBPersistence)):
(IndexedDBThirdPartyDataRemoval)):
(MigrateThirdPartyDataToGeneralStorageDirectory)):
((IndexedDB, IndexedDBGetDatabases)):

Canonical link: https://commits.webkit.org/278769@main

Tools/TestWebKitAPI/Tests/WebKitCocoa/IndexedDBPersistence.mm

@@ -67,12 +67,7 @@ - (void)userContentController:(WKUserContentController *)userContentController d
     NSURLRequest *request = [NSURLRequest requestWithURL:[[NSBundle mainBundle] URLForResource:@"IndexedDBPersistence-1" withExtension:@"html" subdirectory:@"TestWebKitAPI.resources"]];
     [webView loadRequest:request];
 
-    TestWebKitAPI::Util::run(&receivedScriptMessage);
-    receivedScriptMessage = false;
     RetainPtr<NSString> string1 = (NSString *)[getNextMessage() body];
-
-    TestWebKitAPI::Util::run(&receivedScriptMessage);
-    receivedScriptMessage = false;
     RetainPtr<NSString> string2 = (NSString *)[getNextMessage() body];
 
     // Ditch this web view (ditching its web process)
@@ -86,9 +81,6 @@ - (void)userContentController:(WKUserContentController *)userContentController d
 
     request = [NSURLRequest requestWithURL:[[NSBundle mainBundle] URLForResource:@"IndexedDBPersistence-2" withExtension:@"html" subdirectory:@"TestWebKitAPI.resources"]];
     [webView loadRequest:request];
-
-    TestWebKitAPI::Util::run(&receivedScriptMessage);
-    receivedScriptMessage = false;
     RetainPtr<NSString> string3 = (NSString *)[getNextMessage() body];
 
     EXPECT_WK_STREQ(@"UpgradeNeeded", string1.get());
@@ -234,8 +226,6 @@ function postResult(result) {
 static void loadThirdPartyPageInWebView(WKWebView *webView, NSString *expectedResult)
 {
     [webView loadHTMLString:mainFrameStringPersistence baseURL:[NSURL URLWithString:@"http://webkit.org"]];
-    TestWebKitAPI::Util::run(&receivedScriptMessage);
-    receivedScriptMessage = false;
     EXPECT_WK_STREQ(expectedResult, (NSString *)[getNextMessage() body]);
 }
 
@@ -296,8 +286,6 @@ static void loadThirdPartyPageInWebView(WKWebView *webView, NSString *expectedRe
 
     auto secondWebView = adoptNS([[WKWebView alloc] initWithFrame:NSMakeRect(0, 0, 800, 600) configuration:configuration.get()]);
     [secondWebView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"iframe://"]]];
-    TestWebKitAPI::Util::run(&receivedScriptMessage);
-    receivedScriptMessage = false;
     EXPECT_WK_STREQ( @"database is created - put item success", (NSString *)[getNextMessage() body]);
 
     readyToContinue = false;
@@ -423,8 +411,6 @@ static void loadThirdPartyPageInWebView(WKWebView *webView, NSString *expectedRe
         }; \
         </script>";
     [webView loadHTMLString:firstPartyHTMLString baseURL:[NSURL URLWithString:@"http://webkit.org"]];
-    TestWebKitAPI::Util::run(&receivedScriptMessage);
-    receivedScriptMessage = false;
     EXPECT_WK_STREQ(@"database is created", (NSString *)[getNextMessage() body]);
     EXPECT_TRUE([fileManager fileExistsAtPath:webkitOriginFile.path]);
     EXPECT_FALSE([fileManager fileExistsAtPath:wrongWebkitIframeDatabaseDirectory.path]);
@@ -567,19 +553,13 @@ function postDatabases(databases) {
 
     RetainPtr webView = adoptNS([[WKWebView alloc] initWithFrame:NSMakeRect(0, 0, 800, 600) configuration:configuration.get()]);
     [webView loadHTMLString:getDatabasesString baseURL:[NSURL URLWithString:@"http://apple.com"]];
-    TestWebKitAPI::Util::run(&receivedScriptMessage);
-    receivedScriptMessage = false;
     EXPECT_WK_STREQ(@"databases: [{\"name\":\"IndexedDBGetDatabases\",\"version\":1}]", [getNextMessage() body]);
 
     [webView evaluateJavaScript:@"loadFrame()" completionHandler:nil];
-    TestWebKitAPI::Util::run(&receivedScriptMessage);
-    receivedScriptMessage = false;
     EXPECT_WK_STREQ(@"child frame databases: []", [getNextMessage() body]);
 
     RetainPtr secondWebView = adoptNS([[WKWebView alloc] initWithFrame:NSMakeRect(0, 0, 800, 600) configuration:configuration.get()]);
     [secondWebView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"webkit://"]]];
-    TestWebKitAPI::Util::run(&receivedScriptMessage);
-    receivedScriptMessage = false;
     EXPECT_WK_STREQ(@"main frame databases: []", [getNextMessage() body]);
 
     // Getting databases should not create files on disk.