Check whether it has the permission to read files when running ImeTest

Check whether it has the permission to read files when running ImeTest

Sometimes ImeTest fails because it has no permission to read files. We
should check if that's the case.

BUG=651274

[yabinh, 2016-09-28 06:43:45]

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

[commit-bot: I haz the power, 2016-09-28 06:43:52]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[yabinh, 2016-09-28 06:48:46]

yabinh@chromium.org changed reviewers:
+ aelias@chromium.org, changwan@chromium.org

[yabinh, 2016-09-28 06:48:47]

The way to make the test fail on an android phone is:

Go to Settings->Apps->Content Shell->Permissions->Storage, and disable the
permission.

[commit-bot: I haz the power, 2016-09-28 06:59:08]

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

[commit-bot: I haz the power, 2016-09-28 06:59:08]

Dry run: This issue passed the CQ dry run.

[aelias_OOO_until_Jul13, 2016-09-28 23:44:31]

Could you provide a bit of context?
1. Does this turn a flake into a 100% failure, or does it leave the failure rate
unchanged but just provide better information about the reason for the failure?
2. In practice, why are any of our test devices lacking this permission?

[yabinh, 2016-09-29 01:18:32]

Description was changed from

==========
Check whether it has the permission to read files when running ImeTest

Sometimes ImeTest fails because it has no permission to read files. We
should check if that's the case.

BUG=628964
==========

to

==========
Check whether it has the permission to read files when running ImeTest

Sometimes ImeTest fails because it has no permission to read files. We
should check if that's the case.

BUG=651274
==========

[yabinh, 2016-09-29 01:25:31]

On 2016/09/28 23:44:31, aelias wrote:
> Could you provide a bit of context?
> 1. Does this turn a flake into a 100% failure, or does it leave the failure
rate
> unchanged but just provide better information about the reason for the
failure?
> 2. In practice, why are any of our test devices lacking this permission?

#1
Actually it's not a flaky problem. Sorry for the misunderstanding. Opened a new
bug for this issue. Please refer to that bug for details.

#2
AFAIK, it only happens locally when you install content shell for the first
time.

[aelias_OOO_until_Jul13, 2016-09-29 02:20:36]

OK.  This was using run_content_shell_test_apk?  It looks like the code that
script uses to set permissions lives at
https://cs.chromium.org/chromium/src/third_party/catapult/devil/devil/android...
.  Adding this assertion is a marginal improvement, but it would be even better
to fix the bug in the install/run script that causes this to happen.  For
example, perhaps it's a race condition and the activity starts before the
permission setting is complete.  If so, you could cause the test script to
block/poll on the permission setting being complete before starting the test.

If you do add the assertion, I think CriteriaHelper isn't required (just assert
directly) and also ContentDetectionTest should also have it (it's the other test
category that loads files).