Cross-platform DefaultThemeProvider.

chrome/browser/ui/cocoa/themed_window.mm

Index: chrome/browser/ui/cocoa/themed_window.mm
diff --git a/chrome/browser/ui/cocoa/themed_window.mm b/chrome/browser/ui/cocoa/themed_window.mm
index 911bf8af007eb2e69faa27750b18e480b6201b6b..55e9ca32dead7ae60a12ead96f9e14d5eee1afe4 100644
--- a/chrome/browser/ui/cocoa/themed_window.mm
+++ b/chrome/browser/ui/cocoa/themed_window.mm
@@ -4,12 +4,23 @@
 
 #import "chrome/browser/ui/cocoa/themed_window.h"
 
+#include "base/lazy_instance.h"
+#include "ui/base/default_theme_provider.h"
+
+namespace {
+
+// Whether to allow NSExceptions to be raised on the current thread.

[Robert Sesek, 2013/05/17 14:06:37]

?

[groby-ooo-7-16, 2013/05/17 23:52:57]

Overzealous copy/paste on a late night :(
On 2013/05/17 14:06:37, rsesek wrote:

+base::LazyInstance<ui::DefaultThemeProvider>::Leaky
+    g_defaultThemeProvider = LAZY_INSTANCE_INITIALIZER;
+
+}  // namespace
+
 // Default implementations; used mostly for tests so that the hosting windows
 // don't needs to know about the theming machinery.
 @implementation NSWindow (ThemeProvider)
 
 - (ThemeProvider*)themeProvider {
-  return NULL;
+  return &(g_defaultThemeProvider.Get());
 }
 
 - (ThemedWindowStyle)themedWindowStyle {