Add tests against pressing tab when a view controller is presented

ios/chrome/browser/ui/bookmarks/bookmarks_egtest.mm

Index: ios/chrome/browser/ui/bookmarks/bookmarks_egtest.mm
diff --git a/ios/chrome/browser/ui/bookmarks/bookmarks_egtest.mm b/ios/chrome/browser/ui/bookmarks/bookmarks_egtest.mm
index 05a248d039d22119c9b3f60d749870e486afb0de..3bc9c1ab304229dd565f3ac82664e6211d578c71 100644
--- a/ios/chrome/browser/ui/bookmarks/bookmarks_egtest.mm
+++ b/ios/chrome/browser/ui/bookmarks/bookmarks_egtest.mm
@@ -129,6 +129,11 @@ id<GREYMatcher> ActionSheet(Action action) {
 
 }  // namespace
 
+// Expose the first responder.
+@interface UIWindow (FirstResponder)
+- (UIResponder*)firstResponder;
+@end
+
 // Bookmark integration tests for Chrome.
 @interface BookmarksTestCase : ChromeTestCase
 @end
@@ -1265,6 +1270,40 @@ id<GREYMatcher> ActionSheet(Action action) {
       performAction:grey_tap()];
 }
 
+// Tests that hitting the tab key doesn't trigger the omnibox in the background.
+// Testing against regressions of the fix for crbug.com/676993.
+- (void)testTabKeyIsANoOpWhenEditing {
+  const GURL bookmarkURL = web::test::HttpServer::MakeUrl(
+      "http://ios/testing/data/http_server_files/destination.html");
+  NSString* bookmarkTitle = @"Some Bookmark";
+
+  // Load a bookmark into the bookmark model.
+  [BookmarksTestCase addBookmark:bookmarkURL withTitle:bookmarkTitle];
+
+  // Open the bookmark editor.
+  NSString* const kStarLitLabel =
+      !IsCompact() ? l10n_util::GetNSString(IDS_TOOLTIP_STAR)
+                   : l10n_util::GetNSString(IDS_IOS_BOOKMARK_EDIT_SCREEN_TITLE);
+  if (IsCompact()) {
+    [ChromeEarlGreyUI openToolsMenu];
+  }
+  [[EarlGrey selectElementWithMatcher:grey_accessibilityLabel(kStarLitLabel)]
+      performAction:grey_tap()];
+
+  // Hit the tab key.
+  // TODO(crbug.com/695876): Simulate a tab key press with EalrGrey.
+
+  // Verify that the omnibox is not focused.
+  GREYAssertFalse([[[[UIApplication sharedApplication] keyWindow]
+      firstResponder] isKindOfClass:[UITextField class]]);
+}
+
+// Tests that hitting the tab key doesn't trigger the omnibox in the background.
+// Testing against regressions of the fix for crbug.com/676993.
+- (void)testTabKeyIsANoOpWhenSignInPromoIsOpen {
+  TODO
+}
+
 #pragma mark Helper Methods
 
 // Navigates to the bookmark manager UI.