Add ui::GrabDesktopSnapshot for Windows.

ui/snapshot/snapshot.h

Index: ui/snapshot/snapshot.h
diff --git a/ui/snapshot/snapshot.h b/ui/snapshot/snapshot.h
index 356309d86ac6cc10f48bf8c9f716729db47cce41..d6d619041240022534a3690a64a0d189fc47ce83 100644
--- a/ui/snapshot/snapshot.h
+++ b/ui/snapshot/snapshot.h
@@ -29,6 +29,17 @@ SNAPSHOT_EXPORT bool GrabViewSnapshot(
     std::vector<unsigned char>* png_representation,
     const gfx::Rect& snapshot_bounds);
 
+#if defined(OS_WIN)
+
+// Grabs a snapshot of the desktop. No security checks are done.  This is

[sky, 2013/04/16 22:06:49]

If this is for tests, why is it here and not in the test?

[grt (UTC plus 2), 2013/04/17 16:58:17]

Good point. I've moved GrabDesktopShortcut into a new test support lib
(snapshot_test_support). To avoid code duplication, it calls into its own
linked-in copy of the guts of the non-Aura GrabWindowSnapshot.

+// intended to be used for debugging purposes where no BrowserProcess instance
+// is available (ie. tests). DO NOT use in a result of user action.
+SNAPSHOT_EXPORT bool GrabDesktopSnapshot(
+    std::vector<unsigned char>* png_representation,
+    const gfx::Rect& snapshot_bounds);
+
+#endif  // defined(OS_WIN)
+
 }  // namespace ui
 
 #endif  // UI_SNAPSHOT_SNAPSHOT_H_