Apply suggestions from code review

Co-authored-by: Daira Hopwood <daira@jacaranda.org>

zcash_client_backend/src/data_api.rs

@@ -130,7 +130,8 @@ pub trait WalletRead {
         &self,
     ) -> Result<HashMap<AccountId, UnifiedFullViewingKey>, Self::Error>;
 
-    /// Returns all unified full viewing keys known to this wallet.
+    /// Returns the account id corresponding to a given [`UnifiedFullViewingKey`],
+    /// if any.
     fn get_account_for_ufvk(
         &self,
         ufvk: &UnifiedFullViewingKey,
@@ -467,7 +468,6 @@ pub mod testing {
             Ok(HashMap::new())
         }
 
-        /// Returns all unified full viewing keys known to this wallet.
         fn get_account_for_ufvk(
             &self,
             _ufvk: &UnifiedFullViewingKey,

zcash_client_backend/src/data_api/wallet.rs

@@ -122,7 +122,7 @@ where
 /// };
 /// use zcash_proofs::prover::LocalTxProver;
 /// use zcash_client_backend::{
-///     keys::{UnifiedSpendingKey},
+///     keys::UnifiedSpendingKey,
 ///     data_api::{wallet::create_spend_to_address, error::Error, testing},
 ///     wallet::OvkPolicy,
 /// };