cleanup client errors (#771)

substrate/core/client/src/error.rs

@@ -52,22 +52,10 @@ error_chain! {
 			display("Blockchain: {}", e),
 		}
 
-		/// Invalid state data.
-		AuthLenEmpty {
-			description("authority count state error"),
-			display("Current state of blockchain has no authority count value"),
-		}
-
-		/// Invalid state data.
-		AuthEmpty(i: u32) {
-			description("authority value state error"),
-			display("Current state of blockchain has no authority value for index {}", i),
-		}
-
-		/// Invalid state data.
-		AuthLenInvalid {
-			description("authority count state error"),
-			display("Current state of blockchain has invalid authority count value"),
+		/// Invalid authorities set received from the runtime.
+		InvalidAuthoritiesSet {
+			description("authorities set is invalid"),
+			display("Current state of blockchain has invalid authorities set"),
 		}
 
 		/// Cound not get runtime version.
@@ -76,12 +64,6 @@ error_chain! {
 			display("On-chain runtime does not specify version"),
 		}
 
-		/// Invalid state data.
-		AuthInvalid(i: u32) {
-			description("authority value state error"),
-			display("Current state of blockchain has invalid authority value for index {}", i),
-		}
-
 		/// Bad justification for header.
 		BadJustification(h: String) {
 			description("bad justification for header"),
@@ -100,12 +82,6 @@ error_chain! {
 			display("Remote node has responded with invalid header proof"),
 		}
 
-		/// Invalid remote execution proof.
-		InvalidExecutionProof {
-			description("invalid execution proof"),
-			display("Remote node has responded with invalid execution proof"),
-		}
-
 		/// Remote fetch has been cancelled.
 		RemoteFetchCancelled {
 			description("remote fetch cancelled"),