fix(devtools): init devtools in production (#2906)

packages/vue/src/index.ts

@@ -7,7 +7,9 @@ import * as runtimeDom from '@vue/runtime-dom'
 import { isString, NOOP, generateCodeFrame, extend } from '@vue/shared'
 import { InternalRenderFunction } from 'packages/runtime-core/src/component'
 
-__DEV__ && initDev()
+if (__DEV__ || __FEATURE_PROD_DEVTOOLS__) {
+  initDev()
+}
 
 const compileCache: Record<string, RenderFunction> = Object.create(null)
 

packages/vue/src/runtime.ts

@@ -3,7 +3,9 @@
 import { initDev } from './dev'
 import { warn } from '@vue/runtime-dom'
 
-__DEV__ && initDev()
+if (__DEV__ || __FEATURE_PROD_DEVTOOLS__) {
+  initDev()
+}
 
 export * from '@vue/runtime-dom'