Disable sync settings controls for drafts folders

b/11158759
Make the default sync setting for drafts folders 0
(never automatically sync), and disable the settings
control so that it cannot be changed.
Also add a db upgrade step to set any existing drafts
folders to not sync, and clean up any Exchange synced
draft messages.

Change-Id: I256bde231d722089ef2a623482f570a20eccf1de

emailcommon/src/com/android/emailcommon/provider/Mailbox.java

@@ -347,7 +347,9 @@ public class Mailbox extends EmailContent implements MailboxColumns, Parcelable
         SYNCABLE_TYPES = new SparseBooleanArray(7);
         SYNCABLE_TYPES.put(TYPE_INBOX, true);
         SYNCABLE_TYPES.put(TYPE_MAIL, false);
-        SYNCABLE_TYPES.put(TYPE_DRAFTS, true);
+        // TODO: b/11158759
+        // For now, drafts folders are not syncable.
+        //SYNCABLE_TYPES.put(TYPE_DRAFTS, true);
         SYNCABLE_TYPES.put(TYPE_SENT, true);
         SYNCABLE_TYPES.put(TYPE_TRASH, false);
         SYNCABLE_TYPES.put(TYPE_CALENDAR, true);

src/com/android/email/activity/setup/MailboxSettings.java

@@ -192,7 +192,9 @@ public class MailboxSettings extends PreferenceActivity {
             mSyncEnabledPref.setChecked(mMailbox.mSyncInterval != 0);
             mSyncLookbackPref.setValue(String.valueOf(mMailbox.mSyncLookback));
             onDataLoaded();
-            enablePreferences(true);
+            if (mMailbox.mType != Mailbox.TYPE_DRAFTS) {
+                enablePreferences(true);
+            }
         }
     }
 

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

@@ -154,8 +154,8 @@ public final class DBHelper {
     // Version 116: Add MessageMove & MessageStateChange tables.
     // Version 117: Add trigger to delete duplicate messages on sync.
     // Version 118: Set syncInterval to 0 for all IMAP mailboxes
-
-    public static final int DATABASE_VERSION = 118;
+    // Version 119: Disable syncing of DRAFTS type folders.
+    public static final int DATABASE_VERSION = 119;
 
     // Any changes to the database format *must* include update-in-place code.
     // Original version: 2
@@ -1211,6 +1211,29 @@ public final class DBHelper {
                         + mContext.getString(R.string.protocol_imap) + "' or "
                         + HostAuth.TABLE_NAME + "." + HostAuthColumns.PROTOCOL + "='imap'));");
             }
+
+            /**
+             * This statement changes the sync interval column to 0 for all DRAFTS type mailboxes,
+             * and deletes any messages that are:
+             *   * synced from the server, and
+             *   * in an exchange account draft folder
+             *
+             * This is primary for Exchange (b/11158759) but we don't sync draft folders for any
+             * other account type anyway.
+             * This will only affect people who used intermediate builds between email1 and email2,
+             * it should be a no-op for most users.
+             */
+            if (oldVersion <= 118) {
+                db.execSQL("update " + Mailbox.TABLE_NAME + " set " + MailboxColumns.SYNC_INTERVAL
+                        + "=0 where " + MailboxColumns.TYPE + "=" + Mailbox.TYPE_DRAFTS);
+
+                db.execSQL("delete from " + Message.TABLE_NAME + " where "
+                        + "(" + SyncColumns.SERVER_ID + " not null and "
+                        + SyncColumns.SERVER_ID + "!='') and "
+                        + MessageColumns.MAILBOX_KEY + " in (select "
+                        + MailboxColumns.ID + " from " + Mailbox.TABLE_NAME + " where "
+                        + MailboxColumns.TYPE + "=" + Mailbox.TYPE_DRAFTS + ")");
+            }
         }
 
         @Override