fix relative @HtmlImport paths in deep folders in deployment mode

lib/src/normalize_path.dart

Index: lib/src/normalize_path.dart
diff --git a/lib/src/normalize_path.dart b/lib/src/normalize_path.dart
index bac6b8b5ba02bf0c082f553cd988f935874bffde..129dfe63e4cd59ada22297630c055dbc63471f9a 100644
--- a/lib/src/normalize_path.dart
+++ b/lib/src/normalize_path.dart
@@ -13,16 +13,13 @@ String normalizeHtmlImportPath(
   }
 
   var dartFileDir = path.url.dirname(dartFilePath);
-  var segments = path.url.split(dartFileDir);
-  // The dartFileDir without the leading dir (web, lib, test, etc).
-  var dartFileSubDir = path.url.joinAll(segments.getRange(1, segments.length));
 
   // Relative paths have no package supplied.
   if (dartFilePackage == null) {
-    return path.url.normalize(path.url.join(dartFileSubDir, filePath));
+    return path.url.normalize(path.url.join(dartFileDir, filePath));
   }
 
   // Only option left is a packages/ path.
   return path.url.normalize(
-      path.url.join('packages/', dartFilePackage, dartFileSubDir, filePath));
+      path.url.join('packages/', dartFilePackage, dartFileDir, filePath));
 }