SYSTEM_ALERT_WINDOW only in debug builds (#23504)

Summary:
SYSTEM_ALERT_WINDOW permission is used only for debug builds to show draw overlay views or show warnings/errors. This permissions is unused in release builds, and there is an issue regarding removing unused permissions on Android build https://github.com/facebook/react-native/issues/5886#issuecomment-464495388. This PR removes SYSTEM_ALERT_WINDOW from all builds bug debug.

[Android] [Changed] - SYSTEM_ALERT_WINDOW permissions available only in debug builds
Pull Request resolved: https://github.com/facebook/react-native/pull/23504

Differential Revision: D14123045

Pulled By: cpojer

fbshipit-source-id: 68829a774ff23c7cb2721076a9d3870405f48fea

template/android/app/src/debug/AndroidManifest.xml

@@ -1,5 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools">
+
+    <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW"/>
+
     <application tools:targetApi="28" tools:ignore="GoogleAppIndexingWarning" android:networkSecurityConfig="@xml/react_native_config" />
 </manifest>

template/android/app/src/main/AndroidManifest.xml

@@ -2,7 +2,6 @@
   package="com.helloworld">
 
     <uses-permission android:name="android.permission.INTERNET" />
-    <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW"/>
 
     <application
       android:name=".MainApplication"