Updates Zoom bubble layout and adds +/- buttons

chrome/browser/ui/cocoa/location_bar/zoom_decoration.mm

Index: chrome/browser/ui/cocoa/location_bar/zoom_decoration.mm
diff --git a/chrome/browser/ui/cocoa/location_bar/zoom_decoration.mm b/chrome/browser/ui/cocoa/location_bar/zoom_decoration.mm
index 0b806763daf4cfd16d27d9b6be759bb259cb240a..96a056e73848f0a1d647ed72bd3e876bc6e5ad75 100644
--- a/chrome/browser/ui/cocoa/location_bar/zoom_decoration.mm
+++ b/chrome/browser/ui/cocoa/location_bar/zoom_decoration.mm
@@ -48,7 +48,7 @@ bool ZoomDecoration::UpdateIfNecessary(zoom::ZoomController* zoom_controller,
   }
 
   BOOL old_visibility = IsVisible();
-  SetVisible(ShouldShowDecoration() && !zoom_controller->IsAtDefaultZoom());
+  SetVisible(true);
 
   base::string16 zoom_percent =
       base::FormatPercent(zoom_controller->GetZoomPercent());
@@ -127,15 +127,10 @@ void ZoomDecoration::HideUI() {
 void ZoomDecoration::UpdateUI(zoom::ZoomController* zoom_controller,
                               NSString* tooltip_string,
                               bool location_bar_is_dark) {
-  vector_icon_ = nullptr;
-  zoom::ZoomController::RelativeZoom relative_zoom =
-      zoom_controller->GetZoomRelativeToDefault();
-  // There is no icon at the default zoom factor.
-  if (relative_zoom == zoom::ZoomController::ZOOM_BELOW_DEFAULT_ZOOM) {
-    vector_icon_ = &kZoomMinusIcon;
-  } else if (relative_zoom == zoom::ZoomController::ZOOM_ABOVE_DEFAULT_ZOOM) {
-    vector_icon_ = &kZoomPlusIcon;
-  }
+  vector_icon_ = zoom_controller->GetZoomRelativeToDefault() ==
+                         zoom::ZoomController::ZOOM_BELOW_DEFAULT_ZOOM
+                     ? &kZoomMinusIcon
+                     : &kZoomPlusIcon;
 
   SetImage(GetMaterialIcon(location_bar_is_dark));