Ash: Update tab strip for new image assets

Ash: Update tab strip for new image assets

* Metrics changes for new art.
* Allow clicks in the shadow above each tab (4 pixels) to drag the window if the window is restored.  This maintains a large click target for dragging.  When the window is maximized, let that area select the tab since the window cannot be dragged.
* Remove some unused constants.

BUG=117431
TEST=Open multiple tabs and check visual appearance for normal window, incognito window, maximized window.  Also apply a theme and check again.
R=sky@chromium.org


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=128160

[James Cook, 2012-03-21 16:33:21]

Scott, PTAL.  The only interesting bit is in browser_non_client_frame_view.cc
NonClientHitTest() where I redirect some clicks into the caption.  Andre is an
hour or two away from the final assets, so I'll land those then send try jobs
for this patch.

[sky, 2012-03-21 17:11:43]

LGTM

[commit-bot: I haz the power, 2012-03-21 22:00:44]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/jamescook@chromium.org/9814013/14

[commit-bot: I haz the power, 2012-03-22 00:42:43]

Try job failure for 9814013-14 (retry) on win_rel for step "ui_tests".
It's a second try, previously, step "ui_tests" failed.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2012-03-22 02:27:40]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/jamescook@chromium.org/9814013/14

[commit-bot: I haz the power, 2012-03-22 03:32:11]

Change committed as 128160