Rename File.readAsText to File.readAsString. There is no Text type in Dart

sdk/lib/io/file_impl.dart

Index: sdk/lib/io/file_impl.dart
diff --git a/sdk/lib/io/file_impl.dart b/sdk/lib/io/file_impl.dart
index 63c161b3138389ac7edf097929b35d07372d2913..27bace995b50e412281ca066dbcb67b349dc88fc 100644
--- a/sdk/lib/io/file_impl.dart
+++ b/sdk/lib/io/file_impl.dart
@@ -609,7 +609,7 @@ class _File extends _FileBase implements File {
     return result;
   }
 
-  Future<String> readAsText([Encoding encoding = Encoding.UTF_8]) {
+  Future<String> readAsString([Encoding encoding = Encoding.UTF_8]) {
     _ensureFileService();
     return readAsBytes().transform((bytes) {
       if (bytes.length == 0) return "";
@@ -619,7 +619,7 @@ class _File extends _FileBase implements File {
     });
   }
 
-  String readAsTextSync([Encoding encoding = Encoding.UTF_8]) {
+  String readAsStringSync([Encoding encoding = Encoding.UTF_8]) {
     var decoder = _StringDecoders.decoder(encoding);
     List<int> bytes = readAsBytesSync();
     if (bytes.length == 0) return "";