Auto-size the views version of the options dialog.

views/controls/tabbed_pane/native_tabbed_pane_gtk.cc

Index: views/controls/tabbed_pane/native_tabbed_pane_gtk.cc
diff --git a/views/controls/tabbed_pane/native_tabbed_pane_gtk.cc b/views/controls/tabbed_pane/native_tabbed_pane_gtk.cc
index 8900de35d7fec11ab6c910cf7c92f9b8fe0116d6..25705fcbd5765222cf2b62bf8e45f338348e1dbc 100644
--- a/views/controls/tabbed_pane/native_tabbed_pane_gtk.cc
+++ b/views/controls/tabbed_pane/native_tabbed_pane_gtk.cc
@@ -75,6 +75,11 @@ View* NativeTabbedPaneGtk::RemoveTabAtIndex(int index) {
   // widget delete itself when native_view is deleted.
   gtk_notebook_remove_page(GTK_NOTEBOOK(native_view()), index);
 
+  // Removing a tab might change the size of the tabbed pane.
+  RootView* root_view = GetRootView();
+  if (root_view)
+    GetRootView()->Layout();
+
   return removed_tab;
 }
 
@@ -103,6 +108,19 @@ void NativeTabbedPaneGtk::SetFocus() {
   Focus();
 }
 
+gfx::Size NativeTabbedPaneGtk::GetPreferredSize() {
+  if (!native_view())
+    return gfx::Size();
+
+  // For some strange reason (or maybe it's a bug), the requisition is not
+  // returned in the passed requisition parameter, but instead written to the
+  // widget's requisition field.
+  GtkRequisition requisition = { 0, 0 };
+  gtk_widget_size_request(GTK_WIDGET(native_view()), &requisition);
+  GtkRequisition& size(GTK_WIDGET(native_view())->requisition);
+  return gfx::Size(size.width, size.height);
+}
+
 gfx::NativeView NativeTabbedPaneGtk::GetTestingHandle() const {
   return native_view();
 }
@@ -166,6 +184,11 @@ void NativeTabbedPaneGtk::DoAddTabAtIndex(int index, const std::wstring& title,
 
   if (tab_count == 0 && select_if_first_tab)
     gtk_notebook_set_current_page(GTK_NOTEBOOK(native_view()), 0);
+
+  // Relayout the hierarchy, since the added tab might require more space.
+  RootView* root_view = GetRootView();
+  if (root_view)
+    GetRootView()->Layout();
 }
 
 WidgetGtk* NativeTabbedPaneGtk::GetWidgetAt(int index) {