Add a fall-back for novel HTML Elements

Add a fall-back for novel HTML Elements

Browsers keep adding new HTMLElements, the latest is Chrome 25 with
HTMLTemplateElement.  Rather that dying, treat unknown elements as a
plain HTMLElement.  This at least allows access to basic generic
operations, which is often all that is required.

Committed: https://code.google.com/p/dart/source/detail?r=16020

[sra1, 2012-12-12 06:34:56]

This needs to be in M2 for web_ui to run on Chrome 25 which is currently in the
dev channel.

[kasperl, 2012-12-12 06:43:50]

LGTM!

https://codereview.chromium.org/11553015/diff/4001/sdk/lib/_internal/compiler...
File sdk/lib/_internal/compiler/implementation/lib/native_helper.dart (right):

https://codereview.chromium.org/11553015/diff/4001/sdk/lib/_internal/compiler...
sdk/lib/_internal/compiler/implementation/lib/native_helper.dart:240: if (altTag
!= null) {
Nit: I'd try to avoid the abbreviation of alt.

https://codereview.chromium.org/11553015/diff/4001/tests/compiler/dart2js_nat...
File tests/compiler/dart2js_native/native_novel_html_test.dart (right):

https://codereview.chromium.org/11553015/diff/4001/tests/compiler/dart2js_nat...
tests/compiler/dart2js_native/native_novel_html_test.dart:38: print(123);
Is this needed?

https://codereview.chromium.org/11553015/diff/4001/tests/compiler/dart2js_nat...
tests/compiler/dart2js_native/native_novel_html_test.dart:46:
expectNoSuchMethod(action, note) {
Can you use Expect.throws?

[ngeoffray, 2012-12-12 08:14:10]

LGTM

https://codereview.chromium.org/11553015/diff/4001/tests/compiler/dart2js_nat...
File tests/compiler/dart2js_native/native_novel_html_test.dart (right):

https://codereview.chromium.org/11553015/diff/4001/tests/compiler/dart2js_nat...
tests/compiler/dart2js_native/native_novel_html_test.dart:1: // Copyright (c)
2011, the Dart project authors.  Please see the AUTHORS file
2011 is so almost 2 years ago :-)