DeviceUtils.Install: Don't re-grant perms when apk hasn't changed.

DeviceUtils.Install: Don't re-grant perms when apk hasn't changed.

Permission granting is between 1-2 seconds, so saves some time when
running unit tests.

BUG=540857
Committed: https://crrev.com/d88c093b6c403276e864bbf063ed2d040486d31d
Cr-Commit-Position: refs/heads/master@{#353060}

[agrieve, 2015-10-08 00:53:01]

agrieve@chromium.org changed reviewers:
+ jbudorick@chromium.org

[agrieve, 2015-10-08 00:55:13]

On 2015/10/08 00:53:01, agrieve wrote:
> mailto:agrieve@chromium.org changed reviewers:
> + mailto:jbudorick@chromium.org

another possibility for this is to just switch to using adb install -g when
perms are required. If apps want to grant a subset of permissions (does anyone
want to?), they should not use -g and then call GrantPermissions after install.
If there's another reason to not use -g, it'd be good to add in a code comment.

[jbudorick, 2015-10-08 00:58:19]

lgtm

+rnephew

IIRC we looked at install -g and opted to grant the permissions requested by the
APK instead. I don't remember the reason for doing so off the top of my head...
Randy, any idea?

[agrieve, 2015-10-08 01:14:43]

The CQ bit was checked by agrieve@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-10-08 01:15:31]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1388373003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1388373003/1

[commit-bot: I haz the power, 2015-10-08 02:46:03]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-10-08 02:46:04]

Dry run: This issue passed the CQ dry run.

[agrieve, 2015-10-08 15:31:00]

The CQ bit was checked by agrieve@chromium.org

[commit-bot: I haz the power, 2015-10-08 15:34:35]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1388373003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1388373003/1

[commit-bot: I haz the power, 2015-10-08 15:41:27]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-08 15:42:04]

Patchset 1 (id:??) landed as
https://crrev.com/d88c093b6c403276e864bbf063ed2d040486d31d
Cr-Commit-Position: refs/heads/master@{#353060}