Google map is not workign with ionic and windows platform

I built a Cordova Application with ionic framework and need to display Google map.
Everything works fine on Android and iOS. Just on Windows Phone I get the following error: “0x800a1391 - JavaScript runtime error: ‘google’ is undefined”.
I added following code inn html -

Metadat -

meta http-equiv=“Content-Security-Policy” content=“script-src ‘self’ ‘unsafe-inline’ ‘unsafe-eval’”>

script tag for -