Fix a findbugs warning - check file.delete return value.

Fix a findbugs warning - check file.delete return value.

BUG=NONE

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=269960

[nyquist, 2014-05-10 20:47:42]

https://codereview.chromium.org/269603002/diff/40001/base/test/android/javate...
File
base/test/android/javatests/src/org/chromium/base/test/util/TestFileUtil.java
(right):

https://codereview.chromium.org/269603002/diff/40001/base/test/android/javate...
base/test/android/javatests/src/org/chromium/base/test/util/TestFileUtil.java:47:
assert (file.delete() || !file.exists());
Asserts should be side-effect free, similarly to DCHECKs. Could you please put
the result somewhere first, and then assert on that?

Also, if file.delete() returns false, the documentation seems to imply that the
delete failed at that point. Wouldn't !file.exists() always be be false then?

[vandebo (ex-Chrome), 2014-05-12 21:45:58]

https://codereview.chromium.org/269603002/diff/40001/base/test/android/javate...
File
base/test/android/javatests/src/org/chromium/base/test/util/TestFileUtil.java
(right):

https://codereview.chromium.org/269603002/diff/40001/base/test/android/javate...
base/test/android/javatests/src/org/chromium/base/test/util/TestFileUtil.java:47:
assert (file.delete() || !file.exists());
On 2014/05/10 20:47:42, nyquist wrote:
> Asserts should be side-effect free, similarly to DCHECKs. Could you please put
> the result somewhere first, and then assert on that?

Done.

> Also, if file.delete() returns false, the documentation seems to imply that
the
> delete failed at that point. Wouldn't !file.exists() always be be false then?

It could fail because the file doesn't exist and in fact that's why the try job
failed when I just asserted the result.  It seems it can also fail if the
destination is a non-empty directory.  Being that this is test code though, I
think asserting that clean up happened properly makes sense.

[nyquist, 2014-05-12 21:51:07]

lgtm

[vandebo (ex-Chrome), 2014-05-12 21:52:29]

The CQ bit was checked by vandebo@chromium.org

[commit-bot: I haz the power, 2014-05-12 21:53:56]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/vandebo@chromium.org/269603002/60001

[commit-bot: I haz the power, 2014-05-13 01:35:57]

Change committed as 269960