Clean up some messiness in Scopes.

src/scopeinfo.cc

Index: src/scopeinfo.cc
diff --git a/src/scopeinfo.cc b/src/scopeinfo.cc
index 7e7f152597938bb3adc9022078c6fff27ad769ca..e054d7de54f54bf3bf865ff977f5fd3f4a99b270 100644
--- a/src/scopeinfo.cc
+++ b/src/scopeinfo.cc
@@ -37,8 +37,8 @@ namespace internal {
 
 
 static int CompareLocal(Variable* const* v, Variable* const* w) {
-  Slot* s = (*v)->slot();
-  Slot* t = (*w)->slot();
+  Slot* s = (*v)->AsSlot();
+  Slot* t = (*w)->AsSlot();
   // We may have rewritten parameters (that are in the arguments object)
   // and which may have a NULL slot... - find a better solution...
   int x = (s != NULL ? s->index() : 0);
@@ -83,7 +83,7 @@ ScopeInfo<Allocator>::ScopeInfo(Scope* scope)
   for (int i = 0; i < locals.length(); i++) {
     Variable* var = locals[i];
     if (var->is_used()) {
-      Slot* slot = var->slot();
+      Slot* slot = var->AsSlot();
       if (slot != NULL) {
         switch (slot->type()) {
           case Slot::PARAMETER:
@@ -112,9 +112,9 @@ ScopeInfo<Allocator>::ScopeInfo(Scope* scope)
   if (scope->num_heap_slots() > 0) {
     // Add user-defined slots.
     for (int i = 0; i < heap_locals.length(); i++) {
-      ASSERT(heap_locals[i]->slot()->index() - Context::MIN_CONTEXT_SLOTS ==
+      ASSERT(heap_locals[i]->AsSlot()->index() - Context::MIN_CONTEXT_SLOTS ==
              context_slots_.length());
-      ASSERT(heap_locals[i]->slot()->index() - Context::MIN_CONTEXT_SLOTS ==
+      ASSERT(heap_locals[i]->AsSlot()->index() - Context::MIN_CONTEXT_SLOTS ==
              context_modes_.length());
       context_slots_.Add(heap_locals[i]->name());
       context_modes_.Add(heap_locals[i]->mode());
@@ -131,15 +131,15 @@ ScopeInfo<Allocator>::ScopeInfo(Scope* scope)
     Variable* var = scope->function();
     if (var != NULL &&
         var->is_used() &&
-        var->slot()->type() == Slot::CONTEXT) {
+        var->AsSlot()->type() == Slot::CONTEXT) {
       function_name_ = var->name();
       // Note that we must not find the function name in the context slot
       // list - instead it must be handled separately in the
       // Contexts::Lookup() function. Thus record an empty symbol here so we
       // get the correct number of context slots.
-      ASSERT(var->slot()->index() - Context::MIN_CONTEXT_SLOTS ==
+      ASSERT(var->AsSlot()->index() - Context::MIN_CONTEXT_SLOTS ==
              context_slots_.length());
-      ASSERT(var->slot()->index() - Context::MIN_CONTEXT_SLOTS ==
+      ASSERT(var->AsSlot()->index() - Context::MIN_CONTEXT_SLOTS ==
              context_modes_.length());
       context_slots_.Add(Factory::empty_symbol());
       context_modes_.Add(Variable::INTERNAL);