refactor: convert constructor parameter properties for erasableSyntaxOnly compatibility

Signed-off-by: Paul Schultz <pschultz@pobox.com>

packages/frontend-plugin-api/src/analytics/Tracker.ts

@@ -65,13 +65,18 @@ const globalEvents = getOrCreateGlobalSingleton<TempGlobalEvents>(
 export const routableExtensionRenderedEvent = '_ROUTABLE-EXTENSION-RENDERED';
 
 export class Tracker implements AnalyticsTracker {
+  private readonly analyticsApi: AnalyticsApi;
+  private context: AnalyticsContextValue;
+
   constructor(
-    private readonly analyticsApi: AnalyticsApi,
-    private context: AnalyticsContextValue = {
+    analyticsApi: AnalyticsApi,
+    context: AnalyticsContextValue = {
       pluginId: 'root',
       extensionId: 'App',
     },
   ) {
+    this.analyticsApi = analyticsApi;
+    this.context = context;
     // Only register a single beforeunload event across all trackers.
     if (!globalEvents.beforeUnloadRegistered) {
       // Before the page unloads, attempt to capture any deferred navigation

packages/frontend-plugin-api/src/routing/ExternalRouteRef.ts

@@ -71,13 +71,17 @@ class ExternalRouteRefImpl
   implements InternalExternalRouteRef
 {
   readonly $$type = '@backstage/ExternalRouteRef' as any;
+  readonly params: string[];
+  readonly defaultTarget: string | undefined;
 
   constructor(
-    readonly params: string[] = [],
-    readonly defaultTarget: string | undefined,
+    params: string[] = [],
+    defaultTarget: string | undefined,
     creationSite: string,
   ) {
     super(params, creationSite);
+    this.params = params;
+    this.defaultTarget = defaultTarget;
   }
 
   getDefaultTarget() {