Revert of Separate Scope into DeclarationScope and Scope

src/compiler/ast-graph-builder.cc

Index: src/compiler/ast-graph-builder.cc
diff --git a/src/compiler/ast-graph-builder.cc b/src/compiler/ast-graph-builder.cc
index dd89416360a0d8cd029b489a3f09e2fd5528b9be..a3318c7a9b87ee8ce4f678b5c610297cccd779a1 100644
--- a/src/compiler/ast-graph-builder.cc
+++ b/src/compiler/ast-graph-builder.cc
@@ -441,7 +441,7 @@
 
 
 Node* AstGraphBuilder::GetFunctionClosureForContext() {
-  DeclarationScope* closure_scope = current_scope()->GetClosureScope();
+  Scope* closure_scope = current_scope()->ClosureScope();
   if (closure_scope->is_script_scope() ||
       closure_scope->is_module_scope()) {
     // Contexts nested in the native context have a canonical empty function as
@@ -508,7 +508,7 @@
 }
 
 bool AstGraphBuilder::CreateGraph(bool stack_check) {
-  DeclarationScope* scope = info()->scope();
+  Scope* scope = info()->scope();
   DCHECK_NOT_NULL(graph());
 
   // Set up the basic structure of the graph. Outputs for {Start} are the formal
@@ -568,7 +568,7 @@
 
 
 void AstGraphBuilder::CreateGraphBody(bool stack_check) {
-  DeclarationScope* scope = info()->scope();
+  Scope* scope = info()->scope();
 
   // Build the arguments object if it is used.
   BuildArgumentsObject(scope->arguments());
@@ -634,8 +634,8 @@
                                                    : BailoutId::None();
 }
 
-static const char* GetDebugParameterName(Zone* zone, DeclarationScope* scope,
-                                         int index) {
+
+static const char* GetDebugParameterName(Zone* zone, Scope* scope, int index) {
 #if DEBUG
   const AstRawString* name = scope->parameter(index)->raw_name();
   if (name && name->length() > 0) {
@@ -648,8 +648,9 @@
   return nullptr;
 }
 
+
 AstGraphBuilder::Environment::Environment(AstGraphBuilder* builder,
-                                          DeclarationScope* scope,
+                                          Scope* scope,
                                           Node* control_dependency)
     : builder_(builder),
       parameters_count_(scope->num_parameters() + 1),
@@ -3128,7 +3129,7 @@
 
 
 Node* AstGraphBuilder::BuildLocalActivationContext(Node* context) {
-  DeclarationScope* scope = info()->scope();
+  Scope* scope = info()->scope();
 
   // Allocate a new local context.
   Node* local_context = scope->is_script_scope()