Added common layout framework for system menu rows.

ui/views/view.cc

Index: ui/views/view.cc
diff --git a/ui/views/view.cc b/ui/views/view.cc
index 3cb42dca9dab0b6b57422f07348b4cc15293f3fa..d5da6b5b07f827138f42f7776b2f301d3001f928 100644
--- a/ui/views/view.cc
+++ b/ui/views/view.cc
@@ -128,6 +128,10 @@ View::~View() {
 
   ViewStorage::GetInstance()->ViewRemoved(this);
 
+  // Some layout managers hold a reference to the host that they are installed
+  // to and may need to access this during destruction.
+  layout_manager_.reset();
+
   for (Views::const_iterator i(children_.begin()); i != children_.end(); ++i) {
     (*i)->parent_ = NULL;
     if (!(*i)->owned_by_client_)