Change Panel titlebars to activate the panel on click (rather than minimize).
Ctrl/Shift+titlebar-click on a minimized panel continues to restore-all, but
does not minimize-all on an expanded panel anymore.
An explicit minimize/restore button will be used for minimize/restore (separate patches), thus clicking on the titlebar is being changed to focus/restore the panel instead.
BUG=
101217,
118431,
121020,
123176
TEST=Existing tests updated, also verified manually on all platforms.
Committed:
https://src.chromium.org/viewvc/chrome?view=rev&revision=134021