[iOS][MF] Reenable failing keyboard observer test

The disabled test was checking a workaround for when the keyboard
had a cycle of hide/show notifications without actually hiding itself.

On iOS 13 this is fixed.

Mark deprecated API as deprecated.
Reenable test on iOS < 13.

Bug: 1015550
Change-Id: I22931b1df71638bbebb4b11c1a1017317b446c3b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1807325
Auto-Submit: Javier Ernesto Flores Robles <javierrobles@chromium.org>
Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Commit-Queue: Javier Ernesto Flores Robles <javierrobles@chromium.org>
Cr-Commit-Position: refs/heads/master@{#707743}

ios/chrome/browser/ui/autofill/manual_fill/keyboard_observer_egtest.mm

@@ -110,10 +110,15 @@ void TapOnWebElementWithID(const std::string& elementID) {
 }
 
 // Tests the observer correctly identifies when the keyboard stays on screen.
-// TODO(crbug.com/1015550) keyboardDidStayOnScreen is not called on iOS13.
-- (void)DISABLED_testKeyboardDidStayOnScreen {
+- (void)testKeyboardDidStayOnScreen {
+  if (@available(iOS 13, *)) {
+    // On iOS 13 keyboardDidStayOnScreen is not called. This makes the
+    // workaround not needed anymore.
+    return;
+  }
   // Opening the keyboard from a webview blocks EarlGrey's synchronization.
   ScopedSynchronizationDisabler disabler;
+
   // Brings up the keyboard by tapping on one of the form's field.
   TapOnWebElementWithID(kFormElementID1);
 

ios/chrome/browser/ui/util/keyboard_observer_helper.h

@@ -30,7 +30,10 @@ typedef struct {
 
 // Indicates that |UIKeyboardWillHideNotification| was posted but the keyboard
 // was not hidden. For example, this can happen when jumping between fields.
-- (void)keyboardDidStayOnScreen;
+// Deprecated. This is not needed on iOS 13 and will be deleted once support for
+// iOS 12 is removed.
+- (void)keyboardDidStayOnScreen API_DEPRECATED("Not needed on iOS >12",
+                                               ios(11.0, 13.0));
 
 // Indicates that the keyboard state changed, at least on one of the
 // |KeyboardState| aspects.