Set selectionStyle to UITableViewCellSelectionStyleNone for

SettingsSwitchCell.

SettingsSwitchCell should not have a UITableViewCellSelection animation,
so set selectionStyle to UITableViewCellSelectionStyleNone when
configuring SettingsSwitchCell.

Bug: 894791
Change-Id: I21da349f8b888f16af2466d72c1957f17adfe200
Reviewed-on: https://chromium-review.googlesource.com/c/1340260Reviewed-by: edchin <edchin@chromium.org>
Commit-Queue: Yi Su <mrsuyi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#608777}

ios/chrome/browser/ui/settings/cells/settings_switch_item.mm

@@ -47,6 +47,7 @@ const CGFloat kIconImageSize = 28;
   cell.switchView.on = self.on;
   cell.textLabel.textColor =
       [SettingsSwitchCell defaultTextColorForState:cell.switchView.state];
+  cell.selectionStyle = UITableViewCellSelectionStyleNone;
 
   // Update the icon image, if one is present.
   UIImage* iconImage = nil;