Remove worker support of Web SQL Database.

LayoutTests/fast/workers/storage/resources/interrupt-database.js

-var counter = 0;
-function runTransaction()
-{
-    db.transaction(function(tx) {
-        tx.executeSql("INSERT INTO Test VALUES (1)");
-        tx.executeSql("DELETE FROM Test WHERE Foo = 1");
-        if (++counter == 100)
-            postMessage("terminate");
-    }, null, runTransaction);
-}
-
-var db = openDatabase("InterruptDatabaseTest", "1", "", 1);
-db.transaction(function(tx) {
-    tx.executeSql("CREATE TABLE IF NOT EXISTS Test (Foo INT)");
-}, function(error) {
-    postMessage("Error: " + error.message);
-}, function() {
-    runTransaction();
-});