Fix CodeQL static analysis compliance warnings (#7144)

Python/Product/Cookiecutter/Model/FeedTemplateSource.cs

@@ -56,6 +56,7 @@ private async Task BuildCacheAsync() {
             _cache = new List<Template>();
 
             try {
+                ServicePointManager.CheckCertificateRevocationList = true;
                 var client = new WebClient();
                 var feed = await client.DownloadStringTaskAsync(_feedLocation);
                 var feedUrls = feed.Split(new char[] { '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries);

Python/Product/Cookiecutter/Model/GitHubClient.cs

@@ -78,6 +78,7 @@ public async Task<bool> FileExistsAsync(GitHubRepoSearchItem repo, string filePa
         }
 
         private static WebClient CreateClient() {
+            ServicePointManager.CheckCertificateRevocationList = true;
             var wc = new WebClient();
             wc.Encoding = Encoding.UTF8;
             wc.Headers.Add(HttpRequestHeader.UserAgent, UserAgent);

Python/Product/Debugger/Debugger/Transports/WebSocketTransport.cs

@@ -32,6 +32,7 @@ public virtual Stream Connect(Uri uri, bool requireAuthentication) {
             // of inactivity, making it impossible to attach. So before trying to connect to the debugger, "ping" the website
             // via HTTP to ensure that we have something to connect to.
             try {
+                ServicePointManager.CheckCertificateRevocationList = true;
                 var httpRequest = WebRequest.Create(new UriBuilder(uri) { Scheme = "http", Port = -1, Path = "/" }.Uri);
                 httpRequest.Method = WebRequestMethods.Http.Head;
                 httpRequest.Timeout = 5000;

Python/Product/DebuggerHelper/trace.cpp

@@ -481,6 +481,9 @@ static void TraceLine(void* frame) {
 
     void* f_code = ReadField<void*>(frame, fieldOffsets.PyFrameObject.f_code);
     void* co_filename = ReadField<void*>(f_code, fieldOffsets.PyCodeObject.co_filename);
+    if (co_filename == nullptr) {
+        return;
+    }
 
     auto fileNamesOffsets = reinterpret_cast<const int32_t*>(bpData.fileNamesOffsets);
     auto strings = reinterpret_cast<const char*>(bpData.strings);

Python/Product/ProjectWizards/CookiecutterWizard.cs

@@ -143,6 +143,7 @@ private static Uri Resolve(Uri uri) {
                 return uri;
             }
 
+            ServicePointManager.CheckCertificateRevocationList = true;
             var req = WebRequest.CreateHttp(uri);
             req.Method = "HEAD";
             req.AllowAutoRedirect = false;

Python/Product/PythonTools/PythonTools/Project/FtpPublisher.cs

@@ -61,6 +61,7 @@ private static void CopyOneFile(Uri destination, IPublishFile item) {
             EnsureDirectoryExists(rootPath, destinationDir);
 
             // upload the file
+            ServicePointManager.CheckCertificateRevocationList = true;
             FtpWebRequest request = (FtpWebRequest)WebRequest.Create(new Uri(newLoc));
             request.Method = WebRequestMethods.Ftp.UploadFile;
             byte[] buffer = new byte[1024];

Python/Product/PythonTools/PythonTools/Repl/PythonInteractiveEvaluator.CommandProcessorThread.cs

@@ -440,6 +440,8 @@ private void HandleDisplayXaml() {
 
                 _eval.InvokeAsync(() => {
                     try {
+                        // This can potentially instantiate any random subclass of FrameworkElement,
+                        // but that's OK and expected.
                         var fe = XamlReader.Load(new MemoryStream(buffer)) as FrameworkElement;
                         if (fe != null) {
                             _eval.WriteFrameworkElement(fe, fe.DesiredSize);

Python/Product/VSInterpreters/PackageManager/PipPackageCache.cs

@@ -244,6 +244,7 @@ public async Task<PackageSpec> GetPackageInfoAsync(PackageSpec entry, Cancellati
             }
 
             try {
+                ServicePointManager.CheckCertificateRevocationList = true;
                 using (var client = new WebClient()) {
                     Stream data;
                     client.Headers[HttpRequestHeader.UserAgent] = UserAgent;