make SqliteDatabase ConflictAlgorithm and associated methods public.

SQLiteDatabase.java has ConflictAlgorithm which allows callers to specify
actions to take when insert or update causes constraint violations.
These actions are documented at http://www.sqlite.org/lang_conflict.html.

why make these public? usecase is the following:
Gmail has a table with a column "_id" being the integer primary key and
they let sqlite assign key values to the column.
but there is another UNIQUE key column (message_id) in the table.
so an insert could fail due to constraint violation on the message_id column
(i.e., not on the primary key). and when that happens, they would like to
get the value of _id that caused constraint violation.

currently hidden method insertOnConflict() already provides the above
functionality. that means exposing ConflictAlgorithm also.
diff --git a/core/java/android/database/sqlite/SQLiteDatabase.java b/core/java/android/database/sqlite/SQLiteDatabase.java
index 82490bb..e3c25ec 100644
--- a/core/java/android/database/sqlite/SQLiteDatabase.java
+++ b/core/java/android/database/sqlite/SQLiteDatabase.java
@@ -65,9 +65,8 @@
     /**
      * Algorithms used in ON CONFLICT clause
      * http://www.sqlite.org/lang_conflict.html
-     * @hide
      */
-    public enum ConflictAlgorithm {
+    public static final class ConflictAlgorithm {
         /**
          *  When a constraint violation occurs, an immediate ROLLBACK occurs,
          * thus ending the current transaction, and the command aborts with a
@@ -75,14 +74,14 @@
          * (other than the implied transaction that is created on every command)
          *  then this algorithm works the same as ABORT.
          */
-        ROLLBACK("ROLLBACK"),
+        public static final int ROLLBACK = 1;
 
         /**
          * When a constraint violation occurs,no ROLLBACK is executed
          * so changes from prior commands within the same transaction
          * are preserved. This is the default behavior.
          */
-        ABORT("ABORT"),
+        public static final int ABORT = 2;
 
         /**
          * When a constraint violation occurs, the command aborts with a return
@@ -90,7 +89,7 @@
          * the command made prior to encountering the constraint violation
          * are preserved and are not backed out.
          */
-        FAIL("FAIL"),
+        public static final int FAIL = 3;
 
         /**
          * When a constraint violation occurs, the one row that contains
@@ -99,7 +98,7 @@
          * after the row that contained the constraint violation continue to be
          * inserted or updated normally. No error is returned.
          */
-        IGNORE("IGNORE"),
+        public static final int IGNORE = 4;
 
         /**
          * When a UNIQUE constraint violation occurs, the pre-existing rows that
@@ -114,15 +113,16 @@
          * it does not invoke delete triggers on those rows.
          *  This behavior might change in a future release.
          */
-        REPLACE("REPLACE");
+        public static final int REPLACE = 5;
 
-        private final String mValue;
-        ConflictAlgorithm(String value) {
-            mValue = value;
-        }
-        public String value() {
-            return mValue;
-        }
+        /**
+         * use the following when no conflict action is specified.
+         */
+        public static final int NONE = 0;
+        private static final String[] VALUES = new String[]
+                {"", " OR ROLLBACK ", " OR ABORT ", " OR FAIL ", " OR IGNORE ", " OR REPLACE "};
+
+        private ConflictAlgorithm() {}  // disable instantiation of this class
     }
 
     /**
@@ -1334,7 +1334,7 @@
      */
     public long insert(String table, String nullColumnHack, ContentValues values) {
         try {
-            return insertWithOnConflict(table, nullColumnHack, values, null);
+            return insertWithOnConflict(table, nullColumnHack, values, ConflictAlgorithm.NONE);
         } catch (SQLException e) {
             Log.e(TAG, "Error inserting " + values, e);
             return -1;
@@ -1356,7 +1356,7 @@
      */
     public long insertOrThrow(String table, String nullColumnHack, ContentValues values)
             throws SQLException {
-        return insertWithOnConflict(table, nullColumnHack, values, null);
+        return insertWithOnConflict(table, nullColumnHack, values, ConflictAlgorithm.NONE);
     }
 
     /**
@@ -1408,12 +1408,14 @@
      * @param initialValues this map contains the initial column values for the
      *            row. The keys should be the column names and the values the
      *            column values
-     * @param algorithm  {@link ConflictAlgorithm} for insert conflict resolver
-     * @return the row ID of the newly inserted row, or -1 if an error occurred
-     * @hide
+     * @param conflictAlgorithm  {@link ConflictAlgorithm} for insert conflict resolver
+     * @return the row ID of the newly inserted row
+     * OR the primary key of the existing row if the input param 'conflictAlgorithm' =
+     * {@link ConflictAlgorithm#IGNORE}
+     * OR -1 if any error
      */
     public long insertWithOnConflict(String table, String nullColumnHack,
-            ContentValues initialValues, ConflictAlgorithm algorithm) {
+            ContentValues initialValues, int conflictAlgorithm) {
         if (!isOpen()) {
             throw new IllegalStateException("database not open");
         }
@@ -1421,10 +1423,7 @@
         // Measurements show most sql lengths <= 152
         StringBuilder sql = new StringBuilder(152);
         sql.append("INSERT");
-        if (algorithm != null) {
-            sql.append(" OR ");
-            sql.append(algorithm.value());
-        }
+        sql.append(ConflictAlgorithm.VALUES[conflictAlgorithm]);
         sql.append(" INTO ");
         sql.append(table);
         // Measurements show most values lengths < 40
@@ -1548,7 +1547,7 @@
      * @return the number of rows affected
      */
     public int update(String table, ContentValues values, String whereClause, String[] whereArgs) {
-        return updateWithOnConflict(table, values, whereClause, whereArgs, null);
+        return updateWithOnConflict(table, values, whereClause, whereArgs, ConflictAlgorithm.NONE);
     }
 
     /**
@@ -1559,12 +1558,11 @@
      *            valid value that will be translated to NULL.
      * @param whereClause the optional WHERE clause to apply when updating.
      *            Passing null will update all rows.
-     * @param algorithm  {@link ConflictAlgorithm} for update conflict resolver
+     * @param conflictAlgorithm  {@link ConflictAlgorithm} for update conflict resolver
      * @return the number of rows affected
-     * @hide
      */
     public int updateWithOnConflict(String table, ContentValues values,
-            String whereClause, String[] whereArgs, ConflictAlgorithm algorithm) {
+            String whereClause, String[] whereArgs, int conflictAlgorithm) {
         if (!isOpen()) {
             throw new IllegalStateException("database not open");
         }
@@ -1575,12 +1573,7 @@
 
         StringBuilder sql = new StringBuilder(120);
         sql.append("UPDATE ");
-        if (algorithm != null) {
-            sql.append("OR ");
-            sql.append(algorithm.value());
-            sql.append(" ");
-        }
-
+        sql.append(ConflictAlgorithm.VALUES[conflictAlgorithm]);
         sql.append(table);
         sql.append(" SET ");