fix(platform): import InjectionToken and ViewEncapsulation instead of OpaqueToken

COMPILER_OPTIONS is no longer of type OpaqueToken. It is now an InjectionToken parameterized with object with property of type ViewEncapsulation. Introduced by: https://github.com/mhevery/angular/blame/e8778e59231f1a0f37f0ea847a6256398386fa41/tools/public_api_guard/core/index.d.ts#L224-L229

Author: sis0k0

Diff for: nativescript-angular/platform.ts

@@ -16,15 +16,15 @@ import {
 import {
     COMPILER_OPTIONS,
     PlatformRef,
-    OpaqueToken,
+    InjectionToken,
+    ViewEncapsulation,
     createPlatformFactory
 } from "@angular/core";
 
-// Work around a TS bug requiring an import of OpaqueToken without using it
+// Work around a TS bug requiring an imports of InjectionToken and ViewEncapsulation without using them
 if (global.___TS_UNUSED) {
-    (() => {
-        return OpaqueToken;
-    })();
+    (() => InjectionToken)();
+    (() => ViewEncapsulation)();
 }
 
 // Register DOM adapter, if possible. Dynamic platform only!