unique error code for rate-limit

// FREEBIE

src/Messages/OWSMessageSender.m

@@ -434,7 +434,7 @@ NSString *const OWSMessageSenderRateLimitedException = @"RateLimitedException";
         }
 
         if ([exception.name isEqualToString:OWSMessageSenderRateLimitedException]) {
-            NSError *error = OWSErrorWithCodeDescription(OWSErrorCodeUntrustedIdentityKey,
+            NSError *error = OWSErrorWithCodeDescription(OWSErrorCodeSingalServiceRateLimited,
                 NSLocalizedString(@"FAILED_SENDING_BECAUSE_RATE_LIMIT",
                     @"action sheet header when re-sending message which failed because of too many attempts"));
             return failureHandler(error);

src/Util/OWSError.h

@@ -15,6 +15,7 @@ typedef NS_ENUM(NSInteger, OWSErrorCode) {
     OWSErrorCodeFailedToSendOutgoingMessage = 30,
     OWSErrorCodeFailedToDecryptMessage = 100,
     OWSErrorCodeSignalServiceFailure = 1001,
+    OWSErrorCodeSingalServiceRateLimited = 1010,
     OWSErrorCodeUserError = 2001,
 };