flutter: revert patch changes

Signed-off-by: Sunghoon Kang <me@hoon.dev>

pkgs/development/compilers/flutter/patches/flutter3/move-cache.patch

@@ -7,7 +7,7 @@ index dd80b1e46e..8e54517765 100644
  import 'convert.dart';
  import 'features.dart';
 +import 'globals.dart' as globals;
-
+ 
  const String kFlutterRootEnvironmentVariableName = 'FLUTTER_ROOT'; // should point to //flutter/ (root of flutter/flutter repo)
  const String kFlutterEngineEnvironmentVariableName = 'FLUTTER_ENGINE'; // should point to //engine/src/ (root of flutter/engine repo)
 @@ -318,8 +319,13 @@ class Cache {
@@ -26,7 +26,7 @@ index dd80b1e46e..8e54517765 100644
        _lock = lockFile.openSync(mode: FileMode.write);
      } on FileSystemException catch (e) {
 @@ -378,8 +384,7 @@ class Cache {
-
+ 
    String get devToolsVersion {
      if (_devToolsVersion == null) {
 -      const String devToolsDirPath = 'dart-sdk/bin/resources/devtools';
@@ -40,7 +40,7 @@ index 1c31c1b5db..76c7210d3b 100644
 --- a/packages/flutter_tools/lib/src/cache.dart
 +++ b/packages/flutter_tools/lib/src/cache.dart
 @@ -529,6 +529,11 @@ class Cache {
-
+ 
    /// Return the top-level directory in the cache; this is `bin/cache`.
    Directory getRoot() {
 +    const Platform platform = LocalPlatform();