Add filetype icon resources for launcher search result.

Add filetype icon resources for launcher search result.

Previously, Files.app used filetype icons which is prepared to show icons in list/grid view.
However, the resolution is not enough for app launcher search result and it is shown as blurry icon in high-dpi devices.
This CL adds larger icon size resources for app launcher search result.

BUG=490597
TEST=manually tested.

Committed: https://crrev.com/6eaeffc88f5080f56a5de476a56ae139a030798c
Cr-Commit-Position: refs/heads/master@{#333248}

[yawano, 2015-06-08 06:03:03]

yawano@chromium.org changed reviewers:
+ fukino@chromium.org

[yawano, 2015-06-08 06:03:04]

PTAL. Thank you!

[fukino, 2015-06-08 06:26:51]

LGTM

[yawano, 2015-06-08 06:27:25]

On 2015/06/08 06:26:51, fukino wrote:
> LGTM

Thank you!

[yawano, 2015-06-08 06:27:30]

The CQ bit was checked by yawano@chromium.org

[commit-bot: I haz the power, 2015-06-08 06:27:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1163973006/1

[commit-bot: I haz the power, 2015-06-08 07:31:07]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-06-08 07:31:47]

Patchset 1 (id:??) landed as
https://crrev.com/6eaeffc88f5080f56a5de476a56ae139a030798c
Cr-Commit-Position: refs/heads/master@{#333248}