Remove the border when expanding the location bar

This CL makes sure the location bar has the border only during
animations and when the it is contracted.

Bug: 791460
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I12f1edcfe7e1c674b07826ed9e01c46c4cdee8e2
Reviewed-on: https://chromium-review.googlesource.com/809152Reviewed-by: Elodie Banel <lod@chromium.org>
Commit-Queue: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#522115}

ios/chrome/browser/ui/toolbar/clean/toolbar_view_controller.mm

@@ -134,6 +134,13 @@
     self.contractButton.hidden = NO;
     self.contractButton.alpha = 1;
   }];
+  [animator addCompletion:^(UIViewAnimatingPosition finalPosition) {
+    CGFloat borderWidth = (finalPosition == UIViewAnimatingPositionEnd)
+                              ? 0
+                              : kLocationBarBorderWidth;
+    self.locationBarContainer.layer.borderWidth = borderWidth;
+  }];
+
   self.expanded = YES;
 }
 
@@ -143,6 +150,7 @@
   [NSLayoutConstraint deactivateConstraints:self.expandedToolbarConstraints];
   [NSLayoutConstraint activateConstraints:self.regularToolbarConstraints];
   [animator addAnimations:^{
+    self.locationBarContainer.layer.borderWidth = kLocationBarBorderWidth;
     [self.view layoutIfNeeded];
     self.contractButton.hidden = YES;
     self.contractButton.alpha = 0;