IndexedDB: Treat count of 0 as unbounded for getAll() methods

LayoutTests/storage/indexeddb/index-getallkeys.html

Index: LayoutTests/storage/indexeddb/index-getallkeys.html
diff --git a/LayoutTests/storage/indexeddb/index-getallkeys.html b/LayoutTests/storage/indexeddb/index-getallkeys.html
index 652fbca76d075b29b3b965c76d4e125ef291a4e6..5dd3e1def6bace39a1d2a058033b7b0204dbb5ac 100644
--- a/LayoutTests/storage/indexeddb/index-getallkeys.html
+++ b/LayoutTests/storage/indexeddb/index-getallkeys.html
@@ -182,13 +182,13 @@ doSetup(location.pathname + '-IDBIndex.getAllKeys', 1, function(evt) {
     }, 'Non existent key');
 
     async_test(function(t) {
-      var transaction = connection.transaction('out-of-line', 'readonly');
-      var store = transaction.objectStore('out-of-line');
-      var index = store.index('test_idx');
-      assert_throws(new TypeError(), function () {
-        index.getAllKeys(undefined, 0);
-      }, 'getAllKeys() with maxCount=0 should throw TypeError');
-      t.done();
+      var req = createGetAllKeysRequest(t, 'out-of-line', connection,
+          undefined, 0);
+      req.onsuccess = t.step_func(function(evt) {
+          assert_array_equals(evt.target.result, alphabet,
+              'getAllKeys() should return a..z');
+          t.done();
+      });
     }, 'maxCount=0');
 
     async_test(function(t) {