Add accessibility ID to the icon next to autosuggest drop down for iPads.

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

 // Copyright (c) 2014 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_popup_material_row.h"
 
 #include "base/logging.h"
 #include "base/mac/objc_property_releaser.h"
 #import "ios/chrome/browser/ui/omnibox/truncating_attributed_label.h"
 #include "ios/chrome/browser/ui/rtl_geometry.h"
@@ skipping 107 matching lines @@
       CGRectGetWidth(self.bounds) - kAppendButtonSize -
           kAppendButtonTrailingMargin,
       CGRectGetWidth(self.bounds), floor((_rowHeight - kAppendButtonSize) / 2),
       kAppendButtonSize, kAppendButtonSize);
   _appendButton.frame = LayoutRectGetRect(trailingAccessoryLayout);
 }
 
 - (void)updateLeadingImage:(int)imageID {
   _imageView.image = NativeImage(imageID);
 
+  _imageView.accessibilityIdentifier =
+      [NSString stringWithFormat:@"leading image id %d", imageID];
+
   // Adjust the vertical position based on the current size of the row.
   CGRect frame = _imageView.frame;
   frame.origin.y = floor((_rowHeight - kImageDimensionLength) / 2);
   _imageView.frame = frame;
 }
 
 - (void)updateHighlightBackground:(BOOL)highlighted {
   // Set the background color to match the color of selected table view cells
   // when their selection style is UITableViewCellSelectionStyleGray.
   if (highlighted) {
@@ skipping 34 matching lines @@
   return _textTruncatingLabel.attributedText.string;
 }
 
 - (NSString*)accessibilityValue {
   return _detailTruncatingLabel.hidden
              ? _detailAnswerLabel.attributedText.string
              : _detailTruncatingLabel.attributedText.string;
 }
 
 @end