GitLab

Not called navigation_test_util methods directly from EG tests,
instead use [ChromeEarlGrey loadUrl],
[ChromeEarlGrey loadUrlWithoutWaitingForContent]
and [ChromeEarlGrey isLoading].
Also removed unused "ios/chrome/test/app/navigation_test_util.h" imports
through EG-tests.

This is part of EG1 to EG2 migration, which involves moving EarlGrey code from
app-side helpers into test code. For GREYAsserts, the policy is to take assert-
containing-helpers, modify them to return NSError* with localizedDescription
containing the assert failure (in the event of a failure), and then assert
on the result of the helper on the test side.

Note.
There is a usage of navigation_test_util in ios_internal
https://chrome-internal-review.googlesource.com/c/chrome/ios_internal/+/1240877
will submit it after this cl

Bug: 922813
Change-Id: Iafad97e8c0f7904e34a2af3292fbc03dfb505130
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1590707
Commit-Queue: Maksym Onufriienko <monufriienko@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#660882}