Support Inline StreamSends (#3284)

src/core/api.c

@@ -1108,7 +1108,21 @@ MsQuicStreamSend(
         goto Exit;
     }
 
-    if (QueueOper) {
+    if (!Connection->Settings.SendBufferingEnabled &&
+        Connection->WorkerThreadID == CxPlatCurThreadID()) {
+
+        CXPLAT_PASSIVE_CODE();
+
+        BOOLEAN AlreadyInline = Connection->State.InlineApiExecution;
+        if (!AlreadyInline) {
+            Connection->State.InlineApiExecution = TRUE;
+        }
+        QuicStreamSendFlush(Stream);
+        if (!AlreadyInline) {
+            Connection->State.InlineApiExecution = FALSE;
+        }
+
+    } else if (QueueOper) {
         Oper = QuicOperationAlloc(Connection->Worker, QUIC_OPER_TYPE_API_CALL);
         if (Oper == NULL) {
             Status = QUIC_STATUS_OUT_OF_MEMORY;