Make sure images are loaded before running tests

Make sure images are loaded before running tests

The data URI images began to be decoded asynchronously since
https://crbug.com/514206 was fixed. If tests are run before images are
decoded, the dimension would be wrong.

There was a racing condition between starting the test and decoding the
image, and the tests were flaky. The failure rate could be as high as
10% recently.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests. Due to timing issues, image_loaded
always returned True in 4000 local runs.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).

BUG=
R=mdjones@chromium.org

Committed: 4d66ebb8f592421805397f01b236ceb21742ab35

[wychen, 2017-03-15 21:25:02]

Description was changed from

==========
Make sure images are loaded before running tests

The data URI images are decoded asynchonously, and if tests are run
before images are decoded, the dimension would be wrong.

The failure rate recently could be as high as 10%.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).

BUG=
==========

to

==========
Make sure images are loaded before running tests

The data URI images began to be decoded asynchronously since
https://crbug.com/514206 was fixed. If tests are run before images are
decoded, the dimension would be wrong.

There was a racing condition between starting the test and decoding the
image, and the tests were flaky. The failure rate recently could be as
high as 10%.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).
==========

[wychen, 2017-03-15 21:25:02]

wychen@chromium.org changed reviewers:
+ mdjones@chromium.org

[wychen, 2017-03-15 21:25:10]

PTAL

[wychen, 2017-03-17 00:29:26]

Description was changed from

==========
Make sure images are loaded before running tests

The data URI images began to be decoded asynchronously since
https://crbug.com/514206 was fixed. If tests are run before images are
decoded, the dimension would be wrong.

There was a racing condition between starting the test and decoding the
image, and the tests were flaky. The failure rate recently could be as
high as 10%.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).
==========

to

==========
Make sure images are loaded before running tests

The data URI images began to be decoded asynchronously since
https://crbug.com/514206 was fixed. If tests are run before images are
decoded, the dimension would be wrong.

There was a racing condition between starting the test and decoding the
image, and the tests were flaky. The failure rate recently could be as
high as 10%.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests. Due to timing issues, image_loaded
always returned True in 4000 local runs.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).
==========

[wychen, 2017-03-22 17:26:15]

Description was changed from

==========
Make sure images are loaded before running tests

The data URI images began to be decoded asynchronously since
https://crbug.com/514206 was fixed. If tests are run before images are
decoded, the dimension would be wrong.

There was a racing condition between starting the test and decoding the
image, and the tests were flaky. The failure rate recently could be as
high as 10%.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests. Due to timing issues, image_loaded
always returned True in 4000 local runs.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).
==========

to

==========
Make sure images are loaded before running tests

The data URI images began to be decoded asynchronously since
https://crbug.com/514206 was fixed. If tests are run before images are
decoded, the dimension would be wrong.

There was a racing condition between starting the test and decoding the
image, and the tests were flaky. The failure rate could be as high as
10% recently.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests. Due to timing issues, image_loaded
always returned True in 4000 local runs.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).
==========

[mdjones, 2017-03-22 17:35:05]

lgtm

https://codereview.chromium.org/2755503005/diff/1/run_jstests.py
File run_jstests.py (right):

https://codereview.chromium.org/2755503005/diff/1/run_jstests.py#newcode70
run_jstests.py:70: while not driver.execute_script(image_loaded):
I'd check to see if there is a execute-and-wait version of this so we don't need
the timer.

[wychen, 2017-04-11 00:22:55]

https://codereview.chromium.org/2755503005/diff/1/run_jstests.py
File run_jstests.py (right):

https://codereview.chromium.org/2755503005/diff/1/run_jstests.py#newcode70
run_jstests.py:70: while not driver.execute_script(image_loaded):
On 2017/03/22 17:35:04, mdjones wrote:
> I'd check to see if there is a execute-and-wait version of this so we don't
need
> the timer.

I gave selenium.webdriver.support.expected_conditions a try, but strangely,
waiting for a state specified in the image onload handler doesn't guarantee the
image to be decoded already. The failure rate is about 2/1000. Might be some
strange timing issue, but I haven't figured out why.

Given the failure rate of current impl is <1/1000, I'll just go with this one.

[wychen, 2017-04-11 00:28:57]

Description was changed from

==========
Make sure images are loaded before running tests

The data URI images began to be decoded asynchronously since
https://crbug.com/514206 was fixed. If tests are run before images are
decoded, the dimension would be wrong.

There was a racing condition between starting the test and decoding the
image, and the tests were flaky. The failure rate could be as high as
10% recently.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests. Due to timing issues, image_loaded
always returned True in 4000 local runs.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).
==========

to

==========
Make sure images are loaded before running tests

The data URI images began to be decoded asynchronously since
https://crbug.com/514206 was fixed. If tests are run before images are
decoded, the dimension would be wrong.

There was a racing condition between starting the test and decoding the
image, and the tests were flaky. The failure rate could be as high as
10% recently.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests. Due to timing issues, image_loaded
always returned True in 4000 local runs.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).

BUG=
==========

[wychen, 2017-04-11 00:29:20]

Description was changed from

==========
Make sure images are loaded before running tests

The data URI images began to be decoded asynchronously since
https://crbug.com/514206 was fixed. If tests are run before images are
decoded, the dimension would be wrong.

There was a racing condition between starting the test and decoding the
image, and the tests were flaky. The failure rate could be as high as
10% recently.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests. Due to timing issues, image_loaded
always returned True in 4000 local runs.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).

BUG=
==========

to

==========
Make sure images are loaded before running tests

The data URI images began to be decoded asynchronously since
https://crbug.com/514206 was fixed. If tests are run before images are
decoded, the dimension would be wrong.

There was a racing condition between starting the test and decoding the
image, and the tests were flaky. The failure rate could be as high as
10% recently.

Reload the HTML every time before running the tests and make sure they
are loaded before running the tests. Due to timing issues, image_loaded
always returned True in 4000 local runs.

This fixes flakiness in https://crrev.com/2179593002 (commit 6c16f14).

BUG=
R=mdjones@chromium.org

Committed: 4d66ebb8f592421805397f01b236ceb21742ab35
==========

[wychen, 2017-04-11 00:29:22]

Committed patchset #1 (id:1) manually as
4d66ebb8f592421805397f01b236ceb21742ab35 (presubmit successful).