SQL prefixes should be case-insensitive

The new SQL prefix scanner failed to convert the collected prefix to
upper-case.  This meant that lower-case SQL commands were not
correctly categorized.  This has been fixed.

Additional unit tests have been added to test the scanner.

Test : atest
 * FrameworksCoreTests:android.database
 * CtsDatabaseTestCases

Flag: android.database.sqlite.simple_sql_comment_scanner
Bug: 329118560
Change-Id: Idc2980bcf4eb49a0a204ae0cb13748aa3027ede5