Beginning server-side rendering support

samples/react/MusicStore/ReactApp/domain-tasks.ts

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+const domain = require('domain') as any;
+const domainContext = require('domain-context') as any;
+const domainTasksStateKey = '__DOMAIN_TASKS';
+
+export function addTask(task: PromiseLike<any>) {
+    if (task && domain.active) {
+        const state = domainContext.get(domainTasksStateKey) as DomainTasksState;
+        if (state) {
+            state.numRemainingTasks++;
+            task.then(() => {
+                // The application may have other listeners chained to this promise *after*
+                // this listener. Since we don't want the combined task to complete until
+                // all the handlers for child tasks have finished, delay the following by
+                // one tick.
+                setTimeout(() => {
+                    state.numRemainingTasks--;
+                    if (state.numRemainingTasks === 0) {
+                        state.triggerResolved();
+                    }                    
+                }, 0);
+            }, state.triggerRejected);
+        }
+    }
+}
+
+export function run(codeToRun: () => void): Promise<void> {
+    return new Promise((resolve, reject) => {
+        domainContext.runInNewDomain(() => {
+            const state: DomainTasksState = {
+                numRemainingTasks: 0,
+                triggerResolved: resolve,
+                triggerRejected: reject
+            };
+            domainContext.set(domainTasksStateKey, state);
+            codeToRun();
+            
+            // If no tasks were registered synchronously, then we're done already
+            if (state.numRemainingTasks === 0) {
+                resolve();
+            }
+        });
+    }) as any as Promise<void>;
+}
+
+interface DomainTasksState {
+    numRemainingTasks: number;
+    triggerResolved: () => void;
+    triggerRejected: () => void;
+}