Alternate NTP: Fix bug where shadow is not removed

Alternate NTP: Fix bug where shadow is not removed

Opening a link in a new tab from instant search results would cause the instant search result shadow to stay visible.

The problem was that there were three ways the shadow could be hidden:
   (1) -showPreview:..:drawDropShadow:NO
   (2) - hidePreview
   (3) - onActivateTabWithContents:
(1) and (2) correctly hid the shadow but (3) didn't.

Fix was consolidate all the code into (1) and have everyone call that method.

BUG=173778
TEST=See comment 7 in bug 173778 for an easy way to reproduce this bug. Verified that without my fix the shadow is not removed and with my fix the shadow is removed.

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=181865

[sail, 2013-02-11 18:02:32]

dhollowa: ping!

[dhollowa, 2013-02-11 18:14:56]

lgtm

[commit-bot: I haz the power, 2013-02-11 18:18:41]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/sail@chromium.org/12224052/2001

[commit-bot: I haz the power, 2013-02-11 19:22:25]

Retried try job too often on mac_rel for step(s) interactive_ui_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=mac_rel&nu...

[commit-bot: I haz the power, 2013-02-11 19:25:36]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/sail@chromium.org/12224052/2001

[commit-bot: I haz the power, 2013-02-11 20:21:09]

Retried try job too often on mac_rel for step(s) interactive_ui_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=mac_rel&nu...

[commit-bot: I haz the power, 2013-02-11 20:54:46]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/sail@chromium.org/12224052/12001

[commit-bot: I haz the power, 2013-02-11 21:42:16]

Retried try job too often on mac_rel for step(s) interactive_ui_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=mac_rel&nu...

[commit-bot: I haz the power, 2013-02-11 22:07:22]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/sail@chromium.org/12224052/2004

[commit-bot: I haz the power, 2013-02-12 02:23:30]

Retried try job too often on linux_chromeos for step(s) browser_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=linux_chro...

[commit-bot: I haz the power, 2013-02-12 02:33:54]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/sail@chromium.org/12224052/2004