[ios] Fix testSafeModeSendingCrashReport for multitasking.

crrev.com/c/1863950 introduced a visibility check, that causes multitasking
tests to fail.  Since the goal of 1863950 was to migrate to EG2 and keep the
tests the same, removing visibility check here.

Bug: 1016283
TBR: eugenebut@chromium.org
Change-Id: I45e7fff55fce5fd987dc712931809bad442bf164
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1872565
Commit-Queue: Justin Cohen <justincohen@chromium.org>
Auto-Submit: Justin Cohen <justincohen@chromium.org>
Reviewed-by: Jérôme Lebel <jlebel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#707905}

ios/chrome/browser/ui/safe_mode/safe_mode_egtest.mm

@@ -32,8 +32,7 @@ namespace {
 // Verifies that |message| is displayed.
 void AssertMessageOnPage(NSString* message) {
   id<GREYMatcher> messageMatcher =
-      grey_allOf(grey_text(message), grey_kindOfClass([UILabel class]),
-                 grey_sufficientlyVisible(), nil);
+      grey_allOf(grey_text(message), grey_kindOfClass([UILabel class]), nil);
   [[EarlGrey selectElementWithMatcher:messageMatcher]
       assertWithMatcher:grey_notNil()];
 }