fix(server): Ensure all projects that finish ngcc re-enable language service features (#1627)

The implementation of the ngcc queue for re-enabling project language
service's is incorrect. It unconditionally removes projects from the
queue when the ngcc process finishes even if it finished out of order
and is waiting for the first project in the queue to finish. This
results in later projects never getting the language service re-enabled
when the earlier project(s) finally finish ngcc.

This fix works towards stabilizing the extension for solution-style projects.

Related to #876

Author: atscott

server/src/session.ts

@@ -1232,15 +1232,19 @@ export class Session {
     // prioritized for that project's set of files. This will cause issues if the second project is,
     // for example, one that only includes `*.spec.ts` files and not the entire set of files needed
     // to compile the app (i.e. `*.module.ts`).
+    const enabledProjects = new Set<ts.server.Project>();
     for (let i = 0; i < this.projectNgccQueue.length && this.projectNgccQueue[i].done; i++) {
       // Re-enable language service even if ngcc fails, because users could fix
       // the problem by running ngcc themselves. If we keep language service
       // disabled, there's no way users could use the extension even after
       // resolving ngcc issues. On the client side, we will warn users about
       // potentially degraded experience.
-      this.enableLanguageServiceForProject(this.projectNgccQueue[i].project);
+      const p = this.projectNgccQueue[i].project;
+      this.enableLanguageServiceForProject(p);
+      enabledProjects.add(p);
     }
-    this.projectNgccQueue = this.projectNgccQueue.filter(({done}) => !done);
+    this.projectNgccQueue =
+        this.projectNgccQueue.filter(({project}) => !enabledProjects.has(project));
   }
 }