Mark testContextMenuOpenInNewTabFromTallPage FLAKY.

ios/chrome/browser/context_menu/context_menu_egtest.mm

Index: ios/chrome/browser/context_menu/context_menu_egtest.mm
diff --git a/ios/chrome/browser/context_menu/context_menu_egtest.mm b/ios/chrome/browser/context_menu/context_menu_egtest.mm
index 993ebfbae2b35c0dc0e76b5e720c5149b3380eb5..3e021534098550e68294ad48c4449e43f494ca20 100644
--- a/ios/chrome/browser/context_menu/context_menu_egtest.mm
+++ b/ios/chrome/browser/context_menu/context_menu_egtest.mm
@@ -189,7 +189,9 @@ void SelectTabAtIndexInCurrentMode(NSUInteger index) {
 // Tests "Open in New Tab" on context menu  on a link that requires scrolling
 // on the page to verify that context menu can be properly triggered in the
 // current screen view.
-- (void)testContextMenuOpenInNewTabFromTallPage {
+// TODO(crbug.com/701104): This test is flaky because sometimes it doesn't
+// scroll down far enough for the link to be visible.
+- (void)FLAKY_testContextMenuOpenInNewTabFromTallPage {
   // Set up test simple http server.
   std::map<GURL, std::string> responses;
   GURL initialURL =