Gtk3: Use menubar instead of headerbar on version less than 3.10

chrome/browser/ui/libgtkui/gtk_util.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_UI_LIBGTKUI_GTK_UTIL_H_
 #define CHROME_BROWSER_UI_LIBGTKUI_GTK_UTIL_H_
 
 #include <gtk/gtk.h>
 #include <string>
 
@@ skipping 177 matching lines @@
 // context with |context| as the parent.
 ScopedStyleContext AppendCssNodeToStyleContext(GtkStyleContext* context,
                                                const std::string& css_node);
 
 // Parses |css_selector| into a GtkStyleContext.  The format is a
 // sequence of whitespace-separated objects.  Each object may have at
 // most one object name at the beginning of the string, and any number
 // of '.'-prefixed classes and ':'-prefixed pseudoclasses.  An example
 // is "GtkButton.button.suggested-action:hover:active".  The caller
 // must g_object_unref() the returned context.
-ScopedStyleContext GetStyleContextFromCss(const char* css_selector);
+ScopedStyleContext GetStyleContextFromCss(const std::string& css_selector);
 
 SkColor GetFgColorFromStyleContext(GtkStyleContext* context);
 
 // Overrides properties on |context| and all its parents with those
 // provided by |css|.
-void ApplyCssToContext(GtkStyleContext* context, const char* css);
+void ApplyCssToContext(GtkStyleContext* context, const std::string& css);
 
 // Get the 'color' property from the style context created by
 // GetStyleContextFromCss(|css_selector|).
-SkColor GetFgColor(const char* css_selector);
+SkColor GetFgColor(const std::string& css_selector);
 
 // Renders the backgrounds of all ancestors of |context|, then renders
 // the background for |context| itself.
 void RenderBackground(const gfx::Size& size,
                       cairo_t* cr,
                       GtkStyleContext* context);
 
 // Renders a background from the style context created by
 // GetStyleContextFromCss(|css_selector|) into a 24x24 bitmap and
 // returns the average color.
-SkColor GetBgColor(const char* css_selector);
+SkColor GetBgColor(const std::string& css_selector);
 
 // Renders the border from the style context created by
 // GetStyleContextFromCss(|css_selector|) into a 24x24 bitmap and
 // returns the average color.
-SkColor GetBorderColor(const char* css_selector);
+SkColor GetBorderColor(const std::string& css_selector);
 
 // On Gtk3.20 or later, behaves like GetBgColor.  Otherwise, returns
 // the background-color property.
-SkColor GetSelectionBgColor(const char* css_selector);
+SkColor GetSelectionBgColor(const std::string& css_selector);
 
 // Get the color of the GtkSeparator specified by |css_selector|.
-SkColor GetSeparatorColor(const char* css_selector);
+SkColor GetSeparatorColor(const std::string& css_selector);
 #endif
 
 }  // namespace libgtkui
 
 #endif  // CHROME_BROWSER_UI_LIBGTKUI_GTK_UTIL_H_