Avoid duplicate emails in LDAP-based address book

Fixes #3941

NEWS

@@ -24,6 +24,7 @@ Bug fixes
  - [web] fixed display of message content when enabling auto-reply (#3940)
  - [web] don't allow to create lists in a remote address book (not yet supported)
  - [web] fixed attached links in task viewer (#3963)
+ - [web] avoid duplicate mail entries in contact of LDAP-based address book (#3941)
  - [eas] properly skip folders we don't want to synchronize (#3943)
  - [eas] fixed 30 mins freebusy offset with S Planner
  - [eas] now correctly handles reminders on tasks (#3964)

SoObjects/Contacts/NGVCard+SOGo.h

@@ -40,6 +40,7 @@
 
 - (NSString *) workCompany;
 - (NSString *) fullName;
+- (NSArray *) emails;
 - (NSArray *) secondaryEmails;
 
 - (NSString *) workPhone;

SoObjects/Contacts/NGVCard+SOGo.m

@@ -236,6 +236,7 @@ convention:
 - (void) _setEmails: (NSDictionary *) ldifRecord
 {
   CardElement *homeMail;
+  NSString* mail;
 
   // Emails from the configured mail fields of the source have already been extracted in
   // [LDAPSource _fillEmailsOfEntry:intoLDIFRecord:]
@@ -243,9 +244,11 @@ convention:
                    ofType: @"work"
                 withValue: [ldifRecord objectForKey: @"c_emails"]];
   // When importing an LDIF file, add the default mail attribute
-  [self addElementWithTag: @"email"
-                   ofType: @"work"
-                withValue: [ldifRecord objectForKey: @"mail"]];
+  mail = [ldifRecord objectForKey: @"mail"];
+  if ([mail length] && ![[self emails] containsObject: mail])
+    [self addElementWithTag: @"email"
+                     ofType: @"work"
+                  withValue: [ldifRecord objectForKey: @"mail"]];
   homeMail = [self elementWithTag: @"email" ofType: @"home"];
   [homeMail setSingleValue: [ldifRecord objectForKey: @"mozillasecondemail"] forKey: @""];
   [[self uniqueChildWithTag: @"x-mozilla-html"]