Fix upgrade code.

In HC MR2 we introduced a column for a parentKey, but AFAICT, did not
use it. It was populated with a null value. The first upgrade code in
ICS assumed it was '0' which failed to upgrade it properly.

This prevents IMAP accounts from being broken when upgrading from GB ->
ICS.

Bug: 5252620
Change-Id: I000253b7c02ac1706710bdb21a820293f09cbea5

src/com/android/email/mail/store/ImapStore.java

@@ -325,7 +325,7 @@ public class ImapStore extends Store {
             final ImapFolder folder = mailboxes.get(path);
             final Mailbox mailbox = folder.mMailbox;
             int delimiterIdx = mailbox.mServerId.lastIndexOf(mailbox.mDelimiter);
-            long parentKey = -1L;
+            long parentKey = Mailbox.NO_MAILBOX;
             if (delimiterIdx != -1) {
                 String parentPath = path.substring(0, delimiterIdx);
                 final ImapFolder parentFolder = mailboxes.get(parentPath);
@@ -585,12 +585,12 @@ public class ImapStore extends Store {
 
     static class ImapMessage extends MimeMessage {
         ImapMessage(String uid, ImapFolder folder) {
-            this.mUid = uid;
-            this.mFolder = folder;
+            mUid = uid;
+            mFolder = folder;
         }
 
         public void setSize(int size) {
-            this.mSize = size;
+            mSize = size;
         }
 
         @Override
@@ -616,12 +616,12 @@ public class ImapStore extends Store {
 
         public ImapException(String message, String alertText, Throwable throwable) {
             super(message, throwable);
-            this.mAlertText = alertText;
+            mAlertText = alertText;
         }
 
         public ImapException(String message, String alertText) {
             super(message);
-            this.mAlertText = alertText;
+            mAlertText = alertText;
         }
 
         public String getAlertText() {

src/com/android/email/provider/EmailProvider.java

@@ -2400,7 +2400,8 @@ outer:
         // For posterity; this is the command we're executing:
         //sqlite> UPDATE mailbox SET serverid=displayname WHERE mailbox._id in (
         //        ...> SELECT mailbox._id FROM mailbox,account,hostauth WHERE
-        //        ...> mailbox.parentkey=0 AND mailbox.accountkey=account._id AND
+        //        ...> (mailbox.parentkey isnull OR mailbox.parentkey=0) AND
+        //        ...> mailbox.accountkey=account._id AND
         //        ...> account.hostauthkeyrecv=hostauth._id AND
         //        ...> (hostauth.protocol='imap' OR hostauth.protocol='pop3'));
         try {
@@ -2412,7 +2413,10 @@ outer:
                     + Mailbox.TABLE_NAME + "." + MailboxColumns.ID + " FROM "
                     + Mailbox.TABLE_NAME + "," + Account.TABLE_NAME + ","
                     + HostAuth.TABLE_NAME + " WHERE "
-                    + Mailbox.TABLE_NAME + "." + MailboxColumns.PARENT_KEY + "=0 AND "
+                    + "("
+                    + Mailbox.TABLE_NAME + "." + MailboxColumns.PARENT_KEY + " isnull OR "
+                    + Mailbox.TABLE_NAME + "." + MailboxColumns.PARENT_KEY + "=0 "
+                    + ") AND "
                     + Mailbox.TABLE_NAME + "." + MailboxColumns.ACCOUNT_KEY + "="
                     + Account.TABLE_NAME + "." + AccountColumns.ID + " AND "
                     + Account.TABLE_NAME + "." + AccountColumns.HOST_AUTH_KEY_RECV + "="