fix cancelling from imap password prompt r=sspitzer, sr=mscott 111071

mailnews/base/public/msgCore.h

@@ -105,6 +105,8 @@ NS_ERROR_GENERATE_FAILURE(NS_ERROR_MODULE_MAILNEWS, value)
 #define NS_MSG_FAILED(err) \
  (NS_IS_MSG_ERROR(err) && NS_FAILED(err))
 
+#define NS_MSG_PASSWORD_PROMPT_CANCELLED NS_MSG_GENERATE_SUCCESS(1)
+
 /* is this where we define our errors? Obviously, there has to be a central
 	place so we don't use the same error codes.
 */

mailnews/imap/src/nsImapIncomingServer.cpp

@@ -2218,7 +2218,7 @@ NS_IMETHODIMP nsImapIncomingServer::PromptForPassword(char ** aPassword,
     nsresult rv =  GetPasswordWithUI(passwordText, passwordTitle, aMsgWindow,
                                      &okayValue, aPassword);
     nsTextFormatter::smprintf_free(passwordText);
-    return rv;
+    return (okayValue) ? rv : NS_MSG_PASSWORD_PROMPT_CANCELLED;
 }
 
 // for the nsIImapServerSink interface

mailnews/imap/src/nsImapProtocol.cpp

@@ -6564,7 +6564,9 @@ PRBool nsImapProtocol::TryToLogon()
           rv = GetMsgWindow(getter_AddRefs(aMsgWindow));
           if (NS_FAILED(rv)) return rv;
       }
-      m_imapServerSink->PromptForPassword(getter_Copies(password), aMsgWindow);
+      rv = m_imapServerSink->PromptForPassword(getter_Copies(password), aMsgWindow);
+      if (rv == NS_MSG_PASSWORD_PROMPT_CANCELLED)
+        break;
     }
       PRBool imapPasswordIsNew = PR_FALSE;