Dart: Moves |native| methods to patch files.

sky/engine/bindings/builtin.h

Index: sky/engine/bindings/builtin.h
diff --git a/sky/engine/bindings/builtin.h b/sky/engine/bindings/builtin.h
index d1c829bdf4e34124bcafcf1a9c81541cf00d0b1e..c4f0c909d9e7770107cc4cc523ca54ee27db6d55 100644
--- a/sky/engine/bindings/builtin.h
+++ b/sky/engine/bindings/builtin.h
@@ -22,10 +22,21 @@ class Builtin {
     kInvalidLibrary,
   };
 
-  static void SetNativeResolver(BuiltinLibraryId id);
-  static Dart_Handle LoadAndCheckLibrary(BuiltinLibraryId id);
+  // Return the library specified in 'id'.
+  static Dart_Handle GetLibrary(BuiltinLibraryId id);
+
+  // Prepare the library specified in 'id'. Preparation includes:
+  // 1) Setting the native resolver (if any).
+  // 2) Applying patch files (if any).
+  // NOTE: This should only be called once for a library per isolate.
+  static void PrepareLibrary(BuiltinLibraryId id);
 
  private:
+  static int FindResource(const char* path, const uint8_t** resource);
+  static Dart_Handle GetStringResource(const char* resource_name);
+  static void LoadPatchFiles(Dart_Handle library,
+                             const char* patch_uri,
+                             const char** patch_files);
   DISALLOW_IMPLICIT_CONSTRUCTORS(Builtin);
 };