feat(universal): Allow for configuring if preboot complete() is called automatically (immediatelly) or manually (asynchronously)

This is useful if you need to do anything asynchronous (e.g. fetch data) before preboot complete() is called.

Author: steve8708

modules/universal/src/browser/universal-module.ts

@@ -42,6 +42,7 @@ export class OpaqueToken {
 const SharedStylesHost: any = __platform_browser_private__.SharedStylesHost;
 
 export const UNIVERSAL_CACHE = new OpaqueToken('UNIVERSAL_CACHE');
+export const AUTO_PREBOOT = new OpaqueToken('AUTO_PREBOOT');
 
 @NgModule({
   imports: [
@@ -76,16 +77,23 @@ export const UNIVERSAL_CACHE = new OpaqueToken('UNIVERSAL_CACHE');
       },
       deps: []
     },
+    {
+      provide: AUTO_PREBOOT,
+      useValue: true
+    },
     {
       multi: true,
       provide: APP_BOOTSTRAP_LISTENER,
-      useValue: () => {
-        let _win: any = window;
-        if (_win && prebootClient) {
-          setTimeout(() => prebootClient().complete());
-        }
-      }
-    }
+      useFactory: (autoPreboot: boolean) => {
+        return () => {
+          let _win: any = window;
+          if (_win && prebootClient && autoPreboot) {
+            setTimeout(() => prebootClient().complete());
+          }
+        };
+      },
+      deps: [ AUTO_PREBOOT ],
+    },
   ]
 })
 export class UniversalModule {
@@ -101,10 +109,18 @@ export class UniversalModule {
     });
   }
   static withConfig(_config: any = {}): {ngModule: UniversalModule, providers: any[]} {
+    const providers = [];
+
+    if (typeof _config.autoPreboot === 'boolean') {
+      providers.push({
+        provide: AUTO_PREBOOT,
+        useValue: _config.autoPreboot,
+      });
+    }
+
     return {
       ngModule: UniversalModule,
-      providers: [
-      ]
+      providers: providers,
     };
   }
 }