Remove worker support of Web SQL Database.

LayoutTests/fast/workers/storage/resources/open-database-while-transaction-in-progress-sync.js

-function openTestDatabase()
-{
-    return openDatabaseSync("OpenDatabaseWhileTransactionInProgressTest",
-                            "1.0",
-                            "Test to make sure that calling openDatabase() while a transaction is in progress on a different handle to the same database does not result in a deadlock.",
-                            2100000); // 2MB + epsilon
-}
-
-// See https://bugs.webkit.org/show_bug.cgi?id=28207
-// In order to trigger this bug, the transaction must acquire an exclusive
-// lock on the DB file before trying to obtain a second handle to the same DB.
-// The only way to force SQLite to obtain an exclusive lock is to change more
-// than cache_size * page_size bytes in the database. The default value for
-// cache_size is 2000 pages, and the default page_size is 1024 bytes. So the
-// size of the blob must be at least 2MB.
-var db1 = openTestDatabase();
-db1.transaction(function(tx) {
-    tx.executeSql("CREATE TABLE IF NOT EXISTS Test (Foo BLOB);");
-    tx.executeSql("INSERT INTO Test VALUES (ZEROBLOB(2097152));");
-    var db2 = openTestDatabase();
-    postMessage("PASS: second handle opened successfully.");
-
-    // Clean up the DB to allow for repeated runs of this test
-    // without needing to increase the default allowed quota (5MB)
-    tx.executeSql("DELETE FROM Test;");
-});
-
-postMessage("done");