Harden telemetryOnOpenFile against disabled projects

As for syntax-only servers, we can't meaningfully report open-file
telemetry for projects with disabled language services.

Hopefully, a deeper fix will follow, but this solves the immediate
problem that VS disables the LS for all projects when it sees a failure
in applyChangedToOpenFiles (because it assumes the server state is
corrupt).

Author: amcasey

src/server/editorServices.ts

@@ -2777,7 +2777,12 @@ namespace ts.server {
                 return;
             }
 
-            const info: OpenFileInfo = { checkJs: !!scriptInfo.getDefaultProject().getSourceFile(scriptInfo.path)!.checkJsDirective };
+            const project = scriptInfo.getDefaultProject();
+            if (!project.languageServiceEnabled) {
+                return;
+            }       
+
+            const info: OpenFileInfo = { checkJs: !!project.getSourceFile(scriptInfo.path)!.checkJsDirective };
             this.eventHandler({ eventName: OpenFileInfoTelemetryEvent, data: { info } });
         }