XEvent Profiler initial event handlers (#456)

* Bump SMO to 140.2.5 to pick-up private XEvent binaries

* Pick up SMO binaries from the build lab

* Add ProfilerService class placeholder

* Update SMO nuget package to include DB Scoped XEvents

* Stage changes

* Stage changes

* Update SMO to use RTM dependencies and remove separate SqlScript package

* Stage changes

* Iterate on profiler service

* Fix post-merge break in localization

* More refactoring

* Continue iterating on profiler

* Add test profiler listener

* Address a couple of the code review feedback

* Fix AppVeyor build break

* Use self-cleaning test file

src/Microsoft.SqlTools.ServiceLayer/Profiler/XEventSession.cs

@@ -0,0 +1,29 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System.Linq;
+using Microsoft.SqlServer.Management.XEvent;
+using Microsoft.SqlTools.ServiceLayer.Connection;
+using Microsoft.SqlTools.ServiceLayer.Profiler.Contracts;
+
+namespace Microsoft.SqlTools.ServiceLayer.Profiler
+{
+    public class XEventSession : IXEventSession
+    {
+        public Session Session { get; set; }
+
+        public string GetTargetXml()
+        {
+            if (this.Session == null)
+            {
+                return string.Empty;
+            }
+
+            // try to read events from the first target
+            Target defaultTarget = this.Session.Targets.FirstOrDefault();
+            return defaultTarget != null ? defaultTarget.GetTargetData() : string.Empty;
+        }
+    }
+}