Remove widget panel related leftover workspace items

Upgrade launcher DB version and remove items with
widget panel IDs from the database.

Test: follow test instructions (in CL comment)
Bug: 198254728
Change-Id: I077a5f70ee93b7eca738b38f6b0e788d49f7ce70
diff --git a/res/raw/downgrade_schema.json b/res/raw/downgrade_schema.json
index bc25cec..14eac9f 100644
--- a/res/raw/downgrade_schema.json
+++ b/res/raw/downgrade_schema.json
@@ -2,8 +2,9 @@
   // Note: Comments are not supported in JSON schema, but android parser is lenient.
 
   // Maximum DB version supported by this schema
-  "version" : 29,
+  "version" : 30,
 
+  "downgrade_to_29" : [],
   "downgrade_to_28" : [
     "ALTER TABLE favorites RENAME TO temp_favorites;",
     "CREATE TABLE favorites(_id INTEGER PRIMARY KEY, title TEXT, intent TEXT, container INTEGER, screen INTEGER, cellX INTEGER, cellY INTEGER, spanX INTEGER, spanY INTEGER, itemType INTEGER, appWidgetId INTEGER NOT NULL DEFAULT - 1, iconPackage TEXT, iconResource TEXT, icon BLOB, appWidgetProvider TEXT, modified INTEGER NOT NULL DEFAULT 0, restored INTEGER NOT NULL DEFAULT 0, profileId INTEGER DEFAULT 0, rank INTEGER NOT NULL DEFAULT 0, options INTEGER NOT NULL DEFAULT 0);",
diff --git a/src/com/android/launcher3/LauncherProvider.java b/src/com/android/launcher3/LauncherProvider.java
index 49f20c6..df09f29 100644
--- a/src/com/android/launcher3/LauncherProvider.java
+++ b/src/com/android/launcher3/LauncherProvider.java
@@ -97,7 +97,7 @@
      * Represents the schema of the database. Changes in scheme need not be backwards compatible.
      * When increasing the scheme version, ensure that downgrade_schema.json is updated
      */
-    public static final int SCHEMA_VERSION = 29;
+    public static final int SCHEMA_VERSION = 30;
 
     public static final String AUTHORITY = BuildConfig.APPLICATION_ID + ".settings";
     public static final String KEY_LAYOUT_PROVIDER_AUTHORITY = "KEY_LAYOUT_PROVIDER_AUTHORITY";
@@ -864,6 +864,11 @@
                     }
                 }
                 case 29: {
+                    // Remove widget panel related leftover workspace items
+                    db.delete(Favorites.TABLE_NAME, Utilities.createDbSelectionQuery(
+                            Favorites.SCREEN, IntArray.wrap(-777, -778)), null);
+                }
+                case 30: {
                     // DB Upgraded successfully
                     return;
                 }