Start/End handles can have the same direction in mixed LTR/RTL selection

If we have Arabic text in one line and English text in the second line
and select both lines then both touch handles will be right handles
(for RTL reasons). A previous CL (crrev.com/c/658599) assumed that
each handle had to have a different direction. This CL removes that
assumption.

Bug: 766466
Change-Id: Icdb725cc2cf21f593e90d5d90acbd2a489dbca1d
Reviewed-on: https://chromium-review.googlesource.com/678036Reviewed-by: Mohsen Izadi <mohsen@chromium.org>
Reviewed-by: Pedro Amaral <amaralp@chromium.org>
Commit-Queue: Pedro Amaral <amaralp@chromium.org>
Cr-Commit-Position: refs/heads/master@{#504215}

ui/touch_selection/touch_selection_controller.cc

@@ -109,9 +109,9 @@ void TouchSelectionController::OnSelectionBoundsChanged(
   base::AutoReset<InputEventType> auto_reset_response_pending_input_event(
       &response_pending_input_event_, causal_input_event);
 
-  if ((start_orientation_ == TouchHandleOrientation::LEFT &&
-       end_orientation_ == TouchHandleOrientation::RIGHT) ||
-      (start_orientation_ == TouchHandleOrientation::RIGHT &&
+  if ((start_orientation_ == TouchHandleOrientation::LEFT ||
+       start_orientation_ == TouchHandleOrientation::RIGHT) &&
+      (end_orientation_ == TouchHandleOrientation::RIGHT ||
        end_orientation_ == TouchHandleOrientation::LEFT)) {
     OnSelectionChanged();
     return;