Change token to allow undefined return value (#342)

Unauthenticated users won't return a token.

Author: Hinton

crates/bitwarden-wasm-internal/src/client.rs

@@ -21,7 +21,7 @@ pub struct BitwardenClient(pub(crate) Client);
 impl BitwardenClient {
     #[allow(missing_docs)]
     #[wasm_bindgen(constructor)]
-    pub fn new(settings: Option<ClientSettings>, token_provider: JsTokenProvider) -> Self {
+    pub fn new(token_provider: JsTokenProvider, settings: Option<ClientSettings>) -> Self {
         let tokens = Arc::new(WasmClientManagedTokens::new(token_provider));
         Self(Client::new_with_client_tokens(settings, tokens))
     }

crates/bitwarden-wasm-internal/src/platform/token_provider.rs

@@ -5,7 +5,7 @@ use wasm_bindgen::{prelude::wasm_bindgen, JsValue};
 #[wasm_bindgen(typescript_custom_section)]
 const TOKEN_CUSTOM_TS_TYPE: &'static str = r#"
 export interface TokenProvider {
-    get_access_token(): Promise<string>;
+    get_access_token(): Promise<string | undefined>;
 }
 "#;