Changed button type to UIButtonTypeSystem to get default treatment

This gives the image button a pressed state provided by the system.

Bug: 848879
Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
Change-Id: I8912e4cf438a57f27bf432ccb0b1bec10146672c
Reviewed-on: https://chromium-review.googlesource.com/1182669Reviewed-by: Sergio Collazos <sczs@chromium.org>
Commit-Queue: Peter Lee <pkl@chromium.org>
Cr-Commit-Position: refs/heads/master@{#584741}

ios/chrome/browser/ui/autofill/save_card_infobar_view.mm

@@ -284,7 +284,9 @@ UIFont* InfoBarMessageFont() {
   // Add the close button. The close button is fixed to the trailing edge of the
   // infobar since it cannot expand.
   DCHECK(self.closeButtonImage);
-  UIButton* closeButton = [UIButton buttonWithType:UIButtonTypeCustom];
+  UIButton* closeButton =
+      [UIButton buttonWithType:IsRefreshInfobarEnabled() ? UIButtonTypeSystem
+                                                         : UIButtonTypeCustom];
   closeButton.translatesAutoresizingMaskIntoConstraints = NO;
   [closeButton setImage:self.closeButtonImage forState:UIControlStateNormal];
   closeButton.contentEdgeInsets =

ios/chrome/browser/ui/infobars/confirm_infobar_view.mm

@@ -777,7 +777,9 @@ UIImage* InfoBarCloseImage() {
                        action:(SEL)action {
   DCHECK(!closeButton_);
   UIImage* image = InfoBarCloseImage();
-  closeButton_ = [UIButton buttonWithType:UIButtonTypeCustom];
+  closeButton_ =
+      [UIButton buttonWithType:IsRefreshInfobarEnabled() ? UIButtonTypeSystem
+                                                         : UIButtonTypeCustom];
   [closeButton_ setExclusiveTouch:YES];
   [closeButton_ setImage:image forState:UIControlStateNormal];
   [closeButton_ addTarget:target