Support printing scopes in GN

tools/gn/value.cc

Index: tools/gn/value.cc
diff --git a/tools/gn/value.cc b/tools/gn/value.cc
index 3632ddf4a80c5b1cfaab255c00b2467ca92d2cd5..b85eb2d83023c3dc07ef1e7d34bb17d544e57777 100644
--- a/tools/gn/value.cc
+++ b/tools/gn/value.cc
@@ -153,8 +153,22 @@ std::string Value::ToString(bool quote_string) const {
       result.push_back(']');
       return result;
     }
-    case SCOPE:
-      return std::string("<scope>");
+    case SCOPE: {
+      Scope::KeyValueMap scope_values;
+      scope_value_->GetCurrentScopeValues(&scope_values);
+      if (scope_values.empty())
+        return std::string("{ }");
+
+      std::string result = "{\n";
+      for (Scope::KeyValueMap::const_iterator i = scope_values.begin();
+           i != scope_values.end(); ++i) {
+        result += "  " + i->first.as_string() + " = " +
+                  i->second.ToString(true) + "\n";
+      }
+      result += "}";
+
+      return result;
+    }
   }
   return std::string();
 }