Fixes for -Wunused-function on Linux, Android and ChromeOS

chrome/browser/ui/gtk/gtk_chrome_shrinkable_hbox.cc

Index: chrome/browser/ui/gtk/gtk_chrome_shrinkable_hbox.cc
diff --git a/chrome/browser/ui/gtk/gtk_chrome_shrinkable_hbox.cc b/chrome/browser/ui/gtk/gtk_chrome_shrinkable_hbox.cc
index a4b8da62eb35e1bb9b10cdafd367d3938c35141b..1162d216231b52b3c23138d8226d921951ea27fd 100644
--- a/chrome/browser/ui/gtk/gtk_chrome_shrinkable_hbox.cc
+++ b/chrome/browser/ui/gtk/gtk_chrome_shrinkable_hbox.cc
@@ -39,13 +39,6 @@ void SumChildrenWidthRequisition(GtkWidget* child, gpointer userdata) {
   }
 }
 
-void ShowInvisibleChildren(GtkWidget* child, gpointer userdata) {
-  if (!gtk_widget_get_visible(child)) {
-    gtk_widget_show(child);
-    ++(*reinterpret_cast<int*>(userdata));
-  }
-}
-
 void ChildSizeAllocate(GtkWidget* child, gpointer userdata) {
   if (!gtk_widget_get_visible(child))
     return;