fix(backends): ensure currentAppRecord is defined when backend handling components events emitted from Vue. (fix vuejs#1770)

Author: Shaochuan Luo

packages/app-backend-core/src/app.ts

@@ -97,16 +97,16 @@ async function createAppRecord (options: AppRecordOptions, backend: DevtoolsBack
       appRecord: mapAppRecord(record),
     })
 
+    // Auto select first app
+    if (ctx.currentAppRecord == null) {
+      await selectApp(record, ctx)
+    }
+
     if (appRecordPromises.has(options.app)) {
       for (const r of appRecordPromises.get(options.app)) {
         await r(record)
       }
     }
-
-    // Auto select first app
-    if (ctx.currentAppRecord == null) {
-      await selectApp(record, ctx)
-    }
   } else if (SharedData.debugInfo) {
     console.warn('[Vue devtools] No root instance found for app, it might have been unmounted', options.app)
   }