Disallow multiple selection in desktop media picker.

Disallow multiple selection in desktop media picker.

Previously the picker was allowing multiple source selection. Now
DesktopMediaPickerController sets allowsMultipleSelection to NO in
IKImageBrowserView to disable this feature.

BUG=466997
Committed: https://crrev.com/cb535608fda92744d95367cfa2ac9a11c3e49641
Cr-Commit-Position: refs/heads/master@{#330453}

[Sergey Ulanov, 2015-05-18 17:43:51]

sergeyu@chromium.org changed reviewers:
+ dcaiafa@chromium.org, thakis@chromium.org

[Nico, 2015-05-18 17:55:40]

Does this affect picking multiple media files in other places? (Say, image
upload or whatnot)

[Sergey Ulanov, 2015-05-18 18:22:53]

On 2015/05/18 17:55:40, Nico wrote:
> Does this affect picking multiple media files in other places? (Say, image
> upload or whatnot)

How can it affect other places? The flag is set for the ImageBrowserView
instance in the desktop media picker dialog. Is that flag shared between
different instances of that class?

[Nico, 2015-05-18 20:11:41]

I mean "is desktop_media_picker_controller.mm used in any places where multiple
selections are desired?" If not, rs-lgtm

(Sorry if the question doesn't make sense, I'm not familiar with this code.)

[Sergey Ulanov, 2015-05-18 20:14:15]

On 2015/05/18 20:11:41, Nico wrote:
> I mean "is desktop_media_picker_controller.mm used in any places where
multiple
> selections are desired?" If not, rs-lgtm
> 
> (Sorry if the question doesn't make sense, I'm not familiar with this code.)

The code I'm changing is used only for that dialog

[Sergey Ulanov, 2015-05-18 23:17:34]

The CQ bit was checked by sergeyu@chromium.org

[commit-bot: I haz the power, 2015-05-18 23:18:26]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1128353005/1

[commit-bot: I haz the power, 2015-05-19 00:03:35]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-19 00:04:28]

Patchset 1 (id:??) landed as
https://crrev.com/cb535608fda92744d95367cfa2ac9a11c3e49641
Cr-Commit-Position: refs/heads/master@{#330453}