UI must be created before first render, drainMicroTasks when the first page is created (#1103)

Author: PanayotCankov

nativescript-angular/platform-common.ts

@@ -207,16 +207,18 @@ export class NativeScriptPlatformRef extends PlatformRef {
                             reject(err);
                         }
                     });
+
+                    (<any>global).Zone.drainMicroTaskQueue();
                 });
 
                 page.on(Page.navigatingToEvent, initHandler);
 
                 return page;
-            }
+            },
+            animated: false
         };
 
         if (isReboot) {
-            navEntry.animated = false;
             navEntry.clearHistory = true;
         }
 

nativescript-angular/zone-js/dist/zone-nativescript.js

@@ -616,6 +616,7 @@ var Zone$1 = (function (global) {
             _isDrainingMicrotaskQueue = false;
         }
     }
+    Zone.drainMicroTaskQueue = drainMicroTaskQueue;
     function isThenable(value) {
         return value && value.then;
     }
@@ -1576,6 +1577,7 @@ function patchEventTargetMethods(obj, addFnName, removeFnName, metaCreator) {
         return false;
     }
 }
+var originalInstanceKey = zoneSymbol('originalInstance');
 // wrap some native API on `window`