[release/5.0] Http telemetry changes backport (#41610)

* System.Net Telemetry style changes (#41527)

* Change HandshakeStop SslProtocols parameter to enum

* Parameterize Http11/Http20 events

* Add dummy request to ensure Http2 settings are received

* Moved HTTP request telemetry to HttpClient.SendAsync (#41022)

* Moved HTTP request telemetry to HttpClient.SendAsync

* Added ResponseContent and helper methods events.

* Rework helper method activity nesting

* Expand Telemetry tests

* Also log RequestStart/Stop in HttpMessageInvoker

* Update RequestStart signature

* RequestAborted => RequestFailed rename

* ResponseContent Begin => Start/Stop

* Fix HttpMessageInvoker implementation

* Add Synchronous request Telemetry tests

* Check telemetryStarted before ResponseContentStart

Co-authored-by: MihaZupan <mihazupan.zupan1@gmail.com>

* Add Request/Response Headers/Content Start/Stop events (#41590)

Co-authored-by: Marie Píchová <11718369+ManickaP@users.noreply.github.com>

src/libraries/System.Net.Http/src/System/Net/Http/HttpMessageInvoker.cs

@@ -41,7 +41,28 @@ public virtual HttpResponseMessage Send(HttpRequestMessage request,
             }
             CheckDisposed();
 
-            return _handler.Send(request, cancellationToken);
+            if (HttpTelemetry.Log.IsEnabled() && !request.WasSentByHttpClient() && request.RequestUri != null)
+            {
+                HttpTelemetry.Log.RequestStart(request);
+
+                try
+                {
+                    return _handler.Send(request, cancellationToken);
+                }
+                catch when (LogRequestFailed(telemetryStarted: true))
+                {
+                    // Unreachable as LogRequestFailed will return false
+                    throw;
+                }
+                finally
+                {
+                    HttpTelemetry.Log.RequestStop();
+                }
+            }
+            else
+            {
+                return _handler.Send(request, cancellationToken);
+            }
         }
 
         public virtual Task<HttpResponseMessage> SendAsync(HttpRequestMessage request,
@@ -53,7 +74,40 @@ public virtual Task<HttpResponseMessage> SendAsync(HttpRequestMessage request,
             }
             CheckDisposed();
 
+            if (HttpTelemetry.Log.IsEnabled() && !request.WasSentByHttpClient() && request.RequestUri != null)
+            {
+                return SendAsyncWithTelemetry(_handler, request, cancellationToken);
+            }
+
             return _handler.SendAsync(request, cancellationToken);
+
+            static async Task<HttpResponseMessage> SendAsyncWithTelemetry(HttpMessageHandler handler, HttpRequestMessage request, CancellationToken cancellationToken)
+            {
+                HttpTelemetry.Log.RequestStart(request);
+
+                try
+                {
+                    return await handler.SendAsync(request, cancellationToken).ConfigureAwait(false);
+                }
+                catch when (LogRequestFailed(telemetryStarted: true))
+                {
+                    // Unreachable as LogRequestFailed will return false
+                    throw;
+                }
+                finally
+                {
+                    HttpTelemetry.Log.RequestStop();
+                }
+            }
+        }
+
+        internal static bool LogRequestFailed(bool telemetryStarted)
+        {
+            if (HttpTelemetry.Log.IsEnabled() && telemetryStarted)
+            {
+                HttpTelemetry.Log.RequestFailed();
+            }
+            return false;
         }
 
         public void Dispose()

src/libraries/System.Net.Http/src/System/Net/Http/HttpRequestMessage.cs

@@ -14,10 +14,9 @@ public class HttpRequestMessage : IDisposable
     {
         private const int MessageNotYetSent = 0;
         private const int MessageAlreadySent = 1;
-        private const int MessageAlreadySent_StopNotYetCalled = 2;
 
         // Track whether the message has been sent.
-        // The message should only be sent if this field is equal to MessageNotYetSent.
+        // The message shouldn't be sent again if this field is equal to MessageAlreadySent.
         private int _sendStatus = MessageNotYetSent;
 
         private HttpMethod _method;
@@ -201,32 +200,10 @@ private void InitializeValues(HttpMethod method, Uri? requestUri)
 
         internal bool MarkAsSent()
         {
-            return Interlocked.CompareExchange(ref _sendStatus, MessageAlreadySent, MessageNotYetSent) == MessageNotYetSent;
+            return Interlocked.Exchange(ref _sendStatus, MessageAlreadySent) == MessageNotYetSent;
         }
 
-        internal void MarkAsTrackedByTelemetry()
-        {
-            Debug.Assert(_sendStatus != MessageAlreadySent_StopNotYetCalled);
-            _sendStatus = MessageAlreadySent_StopNotYetCalled;
-        }
-
-        internal void OnAborted() => OnStopped(aborted: true);
-
-        internal void OnStopped(bool aborted = false)
-        {
-            if (HttpTelemetry.Log.IsEnabled())
-            {
-                if (Interlocked.Exchange(ref _sendStatus, MessageAlreadySent) == MessageAlreadySent_StopNotYetCalled)
-                {
-                    if (aborted)
-                    {
-                        HttpTelemetry.Log.RequestAborted();
-                    }
-
-                    HttpTelemetry.Log.RequestStop();
-                }
-            }
-        }
+        internal bool WasSentByHttpClient() => _sendStatus == MessageAlreadySent;
 
         #region IDisposable Members
 
@@ -242,8 +219,6 @@ protected virtual void Dispose(bool disposing)
                     _content.Dispose();
                 }
             }
-
-            OnStopped();
         }
 
         public void Dispose()