Removes the space for notification icon if it's not visible (2nd)

ash/system/status_area_widget_delegate.cc

Index: ash/system/status_area_widget_delegate.cc
diff --git a/ash/system/status_area_widget_delegate.cc b/ash/system/status_area_widget_delegate.cc
index f4a7b5ab79d080ef2e53a2454074f56ccf7b8d59..92a8c71730c30bc8a3c6cc580fa590463a4c49b1 100644
--- a/ash/system/status_area_widget_delegate.cc
+++ b/ash/system/status_area_widget_delegate.cc
@@ -83,25 +83,38 @@ void StatusAreaWidgetDelegate::UpdateLayout() {
   views::ColumnSet* columns = layout->AddColumnSet(0);
   if (alignment_ == SHELF_ALIGNMENT_BOTTOM ||
       alignment_ == SHELF_ALIGNMENT_TOP) {
+    bool is_first_visible_child = true;
     for (int c = 0; c < child_count(); ++c) {
-      if (c != 0)
+      views::View* child = child_at(c);
+      if (!child->visible())
+        continue;
+      if (!is_first_visible_child)
         columns->AddPaddingColumn(0, kTraySpacing);
+      is_first_visible_child = false;
       columns->AddColumn(views::GridLayout::CENTER, views::GridLayout::FILL,
                          0, /* resize percent */
                          views::GridLayout::USE_PREF, 0, 0);
     }
     layout->StartRow(0, 0);
-    for (int c = child_count() - 1; c >= 0; --c)
-      layout->AddView(child_at(c));
+    for (int c = child_count() - 1; c >= 0; --c) {
+      views::View* child = child_at(c);
+      if (child->visible())
+        layout->AddView(child);
+    }
   } else {
     columns->AddColumn(views::GridLayout::FILL, views::GridLayout::CENTER,
                        0, /* resize percent */
                        views::GridLayout::USE_PREF, 0, 0);
+    bool is_first_visible_child = true;
     for (int c = child_count() - 1; c >= 0; --c) {
-      if (c != child_count() - 1)
+      views::View* child = child_at(c);
+      if (!child->visible())
+        continue;
+      if (!is_first_visible_child)
         layout->AddPaddingRow(0, kTraySpacing);
+      is_first_visible_child = false;
       layout->StartRow(0, 0);
-      layout->AddView(child_at(c));
+      layout->AddView(child);
     }
   }
   Layout();
@@ -113,6 +126,10 @@ void StatusAreaWidgetDelegate::ChildPreferredSizeChanged(View* child) {
   UpdateWidgetSize();
 }
 
+void StatusAreaWidgetDelegate::ChildVisibilityChanged(View* child) {
+  UpdateLayout();
+}
+
 void StatusAreaWidgetDelegate::UpdateWidgetSize() {
   if (GetWidget())
     GetWidget()->SetSize(GetPreferredSize());