Declares GetHeightForWidth() for those who need it.

Declares GetHeightForWidth() for those who need it.

The default behavior of GetHeightForWidth() just refers GetPreferredSize(),
but views::BoxLayout now calculate the height based on the children.

However, some views use BoxLayout to layout children but want to keep
some specific height by GetPreferredSize(). This doesn't work well anymore,
since BoxLayout just ignores the GetPreferredSize() of the host.
Those views have to override GetHeightForWidth() to keep the preferred height.

BUG=196693
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=193800

[stevenjb, 2013-04-11 18:34:03]

Nice. LGTM

[jennyz, 2013-04-11 18:36:49]

lgtm

[commit-bot: I haz the power, 2013-04-11 20:54:52]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mukai@chromium.org/13925006/1

[commit-bot: I haz the power, 2013-04-11 23:24:46]

Change committed as 193800