[M60 Merge] No AX objects for comments and other irrelevant node types

[M60 Merge] No AX objects for comments and other irrelevant node types

DCHECK was failing for comment node when we try node->ToElement().
Don't create AX objects for comments and other irrelevant node types

Bug: 728185
Change-Id: I377b0cdf0b96e8c0bc805a6f3f0e1f0ed8997749
Reviewed-on: https://chromium-review.googlesource.com/524242
Commit-Queue: Aaron Leventhal <aleventhal@chromium.org>;
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>;
Cr-Commit-Position: refs/heads/master@{#477071}
(cherry picked from commit 7eabf15d969800c61602296bc60fc013fc4e657f)

Review-Url: https://codereview.chromium.org/2974823003 .
Cr-Commit-Position: refs/branch-heads/3112@{#567}
Cr-Branched-From: b6460e24cf59f429d69de255538d0fc7a425ccf9-refs/heads/master@{#474897}
Committed: https://chromium.googlesource.com/chromium/src/+/4cd85345dc057cefc318c3bdb60497d8f0f27911

[awhalley, 2017-07-10 21:43:37]

Description was changed from

==========
[M60 Merge] No AX objects for comments and other irrelevant node types

DCHECK was failing for comment node when we try node->ToElement().
Don't create AX objects for comments and other irrelevant node types

Bug: 728185
Change-Id: I377b0cdf0b96e8c0bc805a6f3f0e1f0ed8997749
Reviewed-on: https://chromium-review.googlesource.com/524242
Commit-Queue: Aaron Leventhal <aleventhal@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#477071}
(cherry picked from commit 7eabf15d969800c61602296bc60fc013fc4e657f)
==========

to

==========
[M60 Merge] No AX objects for comments and other irrelevant node types

DCHECK was failing for comment node when we try node->ToElement().
Don't create AX objects for comments and other irrelevant node types

Bug: 728185
Change-Id: I377b0cdf0b96e8c0bc805a6f3f0e1f0ed8997749
Reviewed-on: https://chromium-review.googlesource.com/524242
Commit-Queue: Aaron Leventhal <aleventhal@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#477071}
(cherry picked from commit 7eabf15d969800c61602296bc60fc013fc4e657f)

Review-Url: https://codereview.chromium.org/2974823003 .
Cr-Commit-Position: refs/branch-heads/3112@{#567}
Cr-Branched-From:
b6460e24cf59f429d69de255538d0fc7a425ccf9-refs/heads/master@{#474897}
Committed:
https://chromium.googlesource.com/chromium/src/+/4cd85345dc057cefc318c3bdb604...
==========

[awhalley, 2017-07-10 21:43:38]

Committed patchset #1 (id:1) manually as
4cd85345dc057cefc318c3bdb60497d8f0f27911.