Add IDBKeyRange to dart:html, port two indexeddb tests

tests/html/html.status

 # Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 event_test: Skip  # Issue 1996
 webgl_1_test: Skip  # Issue 1495
 xmldocument_test: Skip  # XML in dart:html is incomplete
 xmlelement_test: Skip  # XML in dart:html is incomplete
 measurement_test: Pass, Fail  # Issue 1940
 
 [ $compiler == none && ($runtime == drt || $runtime == dartium) ]
 request_animation_frame_test: Skip   # drt hangs; requestAnimationFrame not implemented
+indexeddb_3_test: Fail  # exception not caught - not 'is IDBDatabaseException' ?
+indexeddb_4_test: Fail  # exception not caught - not 'is IDBDatabaseException' ?
 
 [ $compiler == none && ($runtime == drt || $runtime == dartium) && $mode == debug ]
 native_gc_test: Skip  # Issue 2538. Too slow in debug.
 
 [ $compiler == none && $runtime == drt && $system == windows]
 audiocontext_test: Skip
 
 [ $compiler == frog && $runtime == drt ]
 html_test: Skip   # Issue 2657
 request_animation_frame_test: Skip   # drt hangs
@@ skipping 103 matching lines @@
 [ $compiler == frog && $runtime == chrome && $system == windows]
 css_test: Pass, Fail # Test is flaky Issue #2823
 
 # TODO(jmesserly): now that we have a bot, we need to set up Opera testing.
 [ $runtime == opera ]
 *: Skip
 
 [ $compiler == frog && $runtime == none ]
 *: Skip
 
-[ $compiler == dart2js && ($runtime == drt || $runtime == chrome || $runtime == ff) ]
-request_animation_frame_test: Skip # Async test hangs.
-
 [ $compiler == dart2js && $runtime == drt ]
 # Unknown error - should investigate.
 documentfragment_test: Fail
 element_test: Fail
 measurement_test: Fail
 node_test: Fail
 svgelement_test: Fail
 
 [ $compiler == dart2js && $runtime == none ]
 *: Fail, Pass # TODO(ahe): Triage these tests.
 
 [ $compiler == dart2js ]
 dom_isolates_test: Fail # error: cannot resolve spawnDomIsolate
 
 [ $compiler == dart2js && ($runtime == drt || $runtime == chrome || $runtime == ff) ]
+request_animation_frame_test: Skip # Async test hangs.
 isolates_test: Skip   # Timeout because leg does not support web workers.
 typed_arrays_1_test: Fail # dart2js doesn't support is checks with generic types.
 cross_frame_test: Fail # Issue 2774, iframe.contentDocument is accessible in dart:html
 inner_frame_test: Fail # Issue 2774
+indexeddb_3_test: Fail  # TypeError: Object #<IDBCursorWithValue> has no method 'continueFunction'
+indexeddb_4_test: Fail  # TypeError: Object #<IDBCursorWithValue> has no method 'continueFunction'
 
 # DOM errors.
 indexeddb_2_test: Fail # Uncaught error
 window_open_test: Fail # TypeError: Object [object Window] has no method 'close$0'