fix: app端支持tabbar borderStyle自定义色值 (question/150718)

packages/uni-cli-shared/src/json/app/manifest/tabBar.ts

 import { SELECTED_COLOR, TABBAR_HEIGHT } from '@dcloudio/uni-shared'
 
-const TABBAR_WHITE = 'rgba(255,255,255,0.4)'
-const TABBAR_BLACK = 'rgba(0,0,0,0.4)'
+const borderStyles = {
+  black: 'rgba(0,0,0,0.4)',
+  white: 'rgba(255,255,255,0.4)'
+}
 export function initTabBar(
   entryPagePath: string,
   manifestJson: Record<string, any>,
@@ -14,9 +16,9 @@ export function initTabBar(
     JSON.stringify(pagesJson.tabBar)
   ) as UniApp.TabBarOptions
 
-  tabBar.borderStyle = (
-    tabBar.borderStyle === 'white' ? TABBAR_WHITE : TABBAR_BLACK
-  ) as UniApp.TabBarOptions['borderStyle']
+  if (tabBar.borderStyle! in borderStyles) {
+    tabBar.borderStyle = (borderStyles[tabBar.borderStyle!] as UniNamespace.TabBarOptions['borderStyle'])
+  }
 
   if (!tabBar.selectedColor) {
     tabBar.selectedColor = SELECTED_COLOR