[merge] DialogClientView: Fix regression in Chrome Task Manager focusing.

[merge] DialogClientView: Fix regression in Chrome Task Manager focusing.

This CL fixes a regression introduced in
https://codereview.chromium.org/1690133003/. The regression is caused since the
TaskManagerView, adds child views to the DialogClientView. However,
DialogClientView::SetupFocusChain does not account for externally added child
views.

This CL uses View::ReorderChildView to reorder child views and ensure that
appropriate focus order is maintained. Also the redundant contents_ view in
DialogClientViewTest is removed.

BUG=596045, 586419
TBR=karandeepb@chromium.org

Review URL: https://codereview.chromium.org/1826433002

Cr-Commit-Position: refs/heads/master@{#386324}
(cherry picked from commit e5b001fd75dc0fc7dbe265020ffbd84be9916d5c)

Committed: https://chromium.googlesource.com/chromium/src/+/026a1371d6544af1856aa83e3077139a7c2aae39

[tapted, 2016-04-13 00:37:50]

Description was changed from

==========
[merge] DialogClientView: Fix regression in Chrome Task Manager focusing.

This CL fixes a regression introduced in
https://codereview.chromium.org/1690133003/. The regression is caused since the
TaskManagerView, adds child views to the DialogClientView. However,
DialogClientView::SetupFocusChain does not account for externally added child
views.

This CL uses View::ReorderChildView to reorder child views and ensure that
appropriate focus order is maintained. Also the redundant contents_ view in
DialogClientViewTest is removed.

BUG=596045, 586419
TBR=karandeepb@chromium.org

Review URL: https://codereview.chromium.org/1826433002

Cr-Commit-Position: refs/heads/master@{#386324}
(cherry picked from commit e5b001fd75dc0fc7dbe265020ffbd84be9916d5c)
==========

to

==========
[merge] DialogClientView: Fix regression in Chrome Task Manager focusing.

This CL fixes a regression introduced in
https://codereview.chromium.org/1690133003/. The regression is caused since the
TaskManagerView, adds child views to the DialogClientView. However,
DialogClientView::SetupFocusChain does not account for externally added child
views.

This CL uses View::ReorderChildView to reorder child views and ensure that
appropriate focus order is maintained. Also the redundant contents_ view in
DialogClientViewTest is removed.

BUG=596045, 586419
TBR=karandeepb@chromium.org

Review URL: https://codereview.chromium.org/1826433002

Cr-Commit-Position: refs/heads/master@{#386324}
(cherry picked from commit e5b001fd75dc0fc7dbe265020ffbd84be9916d5c)

Committed:
https://chromium.googlesource.com/chromium/src/+/026a1371d6544af1856aa83e3077...
==========

[tapted, 2016-04-13 00:37:54]

Committed patchset #1 (id:1) manually as
026a1371d6544af1856aa83e3077139a7c2aae39.