fix(upgrade): replaces get/setAngularLib with get/setAngularJSGlobal

The current names are confusing because Angular should refer to the latest version of the framework.

tools/public_api_guard/upgrade/static.d.ts

@@ -14,9 +14,15 @@ export declare function downgradeInjectable(token: any): Function;
 export declare function downgradeModule<T>(moduleFactoryOrBootstrapFn: NgModuleFactory<T> | ((extraProviders: StaticProvider[]) => Promise<NgModuleRef<T>>)): string;
 
 /** @stable */
+export declare function getAngularJSGlobal(): any;
+
+/** @deprecated */
 export declare function getAngularLib(): any;
 
 /** @stable */
+export declare function setAngularJSGlobal(ng: any): void;
+
+/** @deprecated */
 export declare function setAngularLib(ng: any): void;
 
 /** @experimental */