Introduce sky_packager

sky/tools/packager/logging.h

Index: sky/tools/packager/logging.h
diff --git a/sky/engine/tonic/dart_error.h b/sky/tools/packager/logging.h
similarity index 50%
copy from sky/engine/tonic/dart_error.h
copy to sky/tools/packager/logging.h
index 52605ce9491a3554920acf0282af1dfb2de20274..227a9d8f5e99c57467bd682bd9d7a886e20d52e3 100644
--- a/sky/engine/tonic/dart_error.h
+++ b/sky/tools/packager/logging.h
@@ -2,20 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef SKY_ENGINE_TONIC_DART_ERROR_H_
-#define SKY_ENGINE_TONIC_DART_ERROR_H_
+#ifndef SKY_TOOLS_PACKAGER_LOGGING_H_
+#define SKY_TOOLS_PACKAGER_LOGGING_H_
 
-#include "dart/runtime/include/dart_api.h"
-
-namespace blink {
+#include <string>
 
-namespace DartError {
-extern const char kInvalidArgument[];
-}  // namespace DartError
+#include "dart/runtime/include/dart_api.h"
 
 bool LogIfError(Dart_Handle handle);
+std::string StringFromDart(Dart_Handle string);
+Dart_Handle StringToDart(const std::string& string);
 
-}  // namespace blink
-
-#endif  // SKY_ENGINE_TONIC_DART_ERROR_H_
-
+#endif  // SKY_TOOLS_PACKAGER_LOGGING_H_