feat: add isCustomElement option (#299)

packages/runtime-core/src/apiApp.ts

@@ -28,6 +28,7 @@ export interface AppConfig {
   devtools: boolean
   performance: boolean
   readonly isNativeTag?: (tag: string) => boolean
+  isCustomElement?: (tag: string) => boolean
   errorHandler?: (
     err: Error,
     instance: ComponentPublicInstance | null,
@@ -62,6 +63,7 @@ export function createAppContext(): AppContext {
       devtools: true,
       performance: false,
       isNativeTag: NO,
+      isCustomElement: NO,
       errorHandler: undefined,
       warnHandler: undefined
     },

packages/runtime-core/src/component.ts

@@ -350,6 +350,7 @@ function finishComponentSetup(
     if (__RUNTIME_COMPILE__ && Component.template && !Component.render) {
       if (compile) {
         Component.render = compile(Component.template, {
+          isCustomElement: instance.appContext.config.isCustomElement || NO,
           onError(err: CompilerError) {
             if (__DEV__) {
               const message = `Template compilation error: ${err.message}`