[ios] Fix omnibox baseWritingDirection and dismissal iOS11 bugs.

ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.h"
 
 #import <CoreText/CoreText.h>
 
 #include "base/command_line.h"
+#include "base/ios/ios_util.h"
 #include "base/logging.h"
 #include "base/mac/foundation_util.h"
 
 #include "base/strings/sys_string_conversions.h"
 #include "components/grit/components_scaled_resources.h"
 #include "components/omnibox/browser/autocomplete_input.h"
 #include "ios/chrome/browser/autocomplete/autocomplete_scheme_classifier_impl.h"
 #import "ios/chrome/browser/ui/animation_util.h"
 #include "ios/chrome/browser/ui/omnibox/omnibox_util.h"
 #import "ios/chrome/browser/ui/reversed_animation.h"
@@ skipping 527 matching lines @@
 - (void)updateTextDirection {
   // Setting the empty field to Natural seems to let iOS update the cursor
   // position when the keyboard language is changed.
   if (![self text].length) {
     [self setTextAlignment:NSTextAlignmentNatural];
     return;
   }
 
   NSTextAlignment alignment = [self bestTextAlignment];
   [self setTextAlignment:alignment];
-  UITextWritingDirection writingDirection =
-      alignment == NSTextAlignmentLeft ? UITextWritingDirectionLeftToRight
-                                       : UITextWritingDirectionRightToLeft;
-  [self
-      setBaseWritingDirection:writingDirection
-                     forRange:[self
-                                  textRangeFromPosition:[self
-                                                            beginningOfDocument]
-                                             toPosition:[self endOfDocument]]];
+  if (!base::ios::IsRunningOnIOS11OrLater()) {
+    // TODO(crbug.com/730461): Remove this entire block once it's been tested
+    // on trunk.
+    UITextWritingDirection writingDirection =
+        alignment == NSTextAlignmentLeft ? UITextWritingDirectionLeftToRight
+                                         : UITextWritingDirectionRightToLeft;
+    [self
+        setBaseWritingDirection:writingDirection
+                       forRange:
+                           [self
+                               textRangeFromPosition:[self beginningOfDocument]
+                                          toPosition:[self endOfDocument]]];
+  }
 }
 
 - (void)setPlaceholder:(NSString*)placeholder {
   if (placeholder && _placeholderTextColor) {
     NSDictionary* attributes =
         @{NSForegroundColorAttributeName : _placeholderTextColor};
     self.attributedPlaceholder =
         [[NSAttributedString alloc] initWithString:placeholder
                                         attributes:attributes];
   } else {
@@ skipping 427 matching lines @@
   // Disable the RTL arrow menu item. The omnibox sets alignment based on the
   // text in the field, and should not be overridden.
   if ([NSStringFromSelector(action) hasPrefix:@"makeTextWritingDirection"]) {
     return NO;
   }
 
   return [super canPerformAction:action withSender:sender];
 }
 
 @end