Include reusable localized text in recipient-not-found error

This way we can use it for calls as well.

// FREEBIE

src/Contacts/ContactsUpdater.h

@@ -10,8 +10,6 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface ContactsUpdater : NSObject
 
-#define NOTFOUND_ERROR 777404
-
 + (instancetype)sharedUpdater;
 
 - (nullable SignalRecipient *)synchronousLookup:(NSString *)identifier error:(NSError **)error;

src/Contacts/ContactsUpdater.m

@@ -66,9 +66,7 @@ NS_ASSUME_NONNULL_BEGIN
                                  if (matchedIds.count == 1) {
                                      success([SignalRecipient recipientWithTextSecureIdentifier:identifier]);
                                  } else {
-                                     failure([NSError errorWithDomain:@"contactsmanager.notfound"
-                                                                 code:NOTFOUND_ERROR
-                                                             userInfo:nil]);
+                                     failure(OWSErrorMakeNoSuchSignalRecipientError());
                                  }
                              }
                              failure:failure];

src/Messages/OWSMessageSender.m

@@ -286,13 +286,12 @@ NSString *const OWSMessageSenderRateLimitedException = @"RateLimitedException";
                 recipient = [self.contactsUpdater synchronousLookup:recipientContactId error:&error];
 
                 if (error) {
-                    if (error.code == NOTFOUND_ERROR) {
-                        DDLogWarn(@"recipient contact not found with error: %@", error);
+                    if (error.code == OWSErrorCodeNoSuchSignalRecipient) {
+                        DDLogWarn(@"%@ recipient contact not found", self.tag);
                         [self unregisteredRecipient:recipient message:message thread:thread];
-                        NSError *error = OWSErrorMakeNoSuchSignalRecipientError();
-                        return failureHandler(error);
                     }
-                    DDLogError(@"contact lookup failed with error: %@", error);
+
+                    DDLogError(@"%@ contact lookup failed with error: %@", self.tag, error);
                     return failureHandler(error);
                 }
             }

src/Util/OWSError.h

@@ -20,6 +20,7 @@ typedef NS_ENUM(NSInteger, OWSErrorCode) {
     OWSErrorCodeSignalServiceFailure = 1001,
     OWSErrorCodeSignalServiceRateLimited = 1010,
     OWSErrorCodeUserError = 2001,
+    OWSErrorCodeNoSuchSignalRecipient = 777404,
 };
 
 extern NSError *OWSErrorWithCodeDescription(OWSErrorCode code, NSString *description);