[Tizen] Temporarily fix unexpected partial repaint (#362)

Author: swift-kim

shell/platform/embedder/embedder.cc

@@ -331,7 +331,7 @@ InferOpenGLPlatformViewCreationCallback(
       return flutter::GLFBOInfo{
           .fbo_id = static_cast<uint32_t>(id),
           .partial_repaint_enabled = false,
-          .existing_damage = SkIRect::MakeEmpty(),
+          .existing_damage = std::nullopt,
       };
     }
 
@@ -340,19 +340,18 @@ InferOpenGLPlatformViewCreationCallback(
     populate_existing_damage(user_data, id, &existing_damage);
 
     bool partial_repaint_enabled = true;
-    SkIRect existing_damage_rect;
+    std::optional<SkIRect> existing_damage_rect;
 
     // Verify that at least one damage rectangle was provided.
     if (existing_damage.num_rects <= 0 || existing_damage.damage == nullptr) {
-      FML_LOG(INFO) << "No damage was provided. Forcing full repaint.";
-      existing_damage_rect = SkIRect::MakeEmpty();
+      existing_damage_rect = std::nullopt;
       partial_repaint_enabled = false;
     } else if (existing_damage.num_rects > 1) {
       // Log message notifying users that multi-damage is not yet available in
       // case they try to make use of it.
       FML_LOG(INFO) << "Damage with multiple rectangles not yet supported. "
                        "Repainting the whole frame.";
-      existing_damage_rect = SkIRect::MakeEmpty();
+      existing_damage_rect = std::nullopt;
       partial_repaint_enabled = false;
     } else {
       existing_damage_rect = FlutterRectToSkIRect(*(existing_damage.damage));