[iOS UI Refresh] fix omnibox layout when input is short.

Fixes the layout of the omnibox when the input is short.

Bug: None
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: Ib5fa70364d805b62d10b9e5e4a4a4b519c341759
Tested: iPhone, iPad, editing and not, rotating, in multitasking.
Reviewed-on: https://chromium-review.googlesource.com/971421Reviewed-by: Gauthier Ambard <gambard@chromium.org>
Commit-Queue: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#544657}

ios/chrome/browser/ui/toolbar/adaptive/primary_toolbar_view.mm

@@ -315,13 +315,7 @@
 
   // locationBarView constraints, if present.
   if (self.locationBarView) {
-    AddSameConstraintsToSides(
-        self.locationBarView, self.locationBarContainer,
-        LayoutSides::kTop | LayoutSides::kBottom | LayoutSides::kLeading);
-    [self.locationBarContainer.trailingAnchor
-        constraintGreaterThanOrEqualToAnchor:self.locationBarView
-                                                 .trailingAnchor]
-        .active = YES;
+    AddSameConstraints(self.locationBarView, self.locationBarContainer);
   }
 
   // Cancel button constraints.
@@ -368,9 +362,7 @@
     return;
 
   [self.locationBarContainer addSubview:locationBarView];
-  AddSameConstraintsToSides(
-      self.locationBarView, self.locationBarContainer,
-      LayoutSides::kTop | LayoutSides::kBottom | LayoutSides::kLeading);
+  AddSameConstraints(self.locationBarView, self.locationBarContainer);
   [self.locationBarContainer.trailingAnchor
       constraintGreaterThanOrEqualToAnchor:self.locationBarView.trailingAnchor]
       .active = YES;