Fix output path for --appSizeBase (#158302)

Fixes https://github.com/flutter/flutter/issues/158211

before

```shell
A summary of your APK analysis can be found at: /Users/lxf/.flutter-devtools/apk-code-size-analysis_01.json

To analyze your app size in Dart DevTools, run the following command:
dart devtools --appSizeBase=apk-code-size-analysis_01.json
```

now

```shell
A summary of your APK analysis can be found at: /Users/lxf/.flutter-devtools/apk-code-size-analysis_01.json

To analyze your app size in Dart DevTools, run the following command:
dart devtools --appSizeBase=/Users/lxf/.flutter-devtools/apk-code-size-analysis_01.json
```


## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [ ] I updated/added relevant documentation (doc comments with `///`).
- [ ] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

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[CLA]: https://cla.developers.google.com/
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[breaking change policy]:
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[Discord]:
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[Data Driven Fixes]:
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Co-authored-by: Kenzie Davisson <43759233+kenzieschmoll@users.noreply.github.com>

packages/flutter_tools/lib/src/android/gradle.dart

@@ -629,14 +629,9 @@ class AndroidGradleBuilder implements AndroidBuilder {
       'A summary of your ${kind.toUpperCase()} analysis can be found at: ${outputFile.path}',
     );
 
-    // DevTools expects a file path relative to the .flutter-devtools/ dir.
-    final String relativeAppSizePath = outputFile.path
-        .split('.flutter-devtools/')
-        .last
-        .trim();
     _logger.printStatus(
         '\nTo analyze your app size in Dart DevTools, run the following command:\n'
-            'dart devtools --appSizeBase=$relativeAppSizePath'
+        'dart devtools --appSizeBase=${outputFile.path}'
     );
   }
 

packages/flutter_tools/lib/src/commands/build_ios.dart

@@ -773,11 +773,9 @@ abstract class _BuildIOSSubCommand extends BuildSubCommand {
         'A summary of your iOS bundle analysis can be found at: ${outputFile.path}',
       );
 
-      // DevTools expects a file path relative to the .flutter-devtools/ dir.
-      final String relativeAppSizePath = outputFile.path.split('.flutter-devtools/').last.trim();
       globals.printStatus(
         '\nTo analyze your app size in Dart DevTools, run the following command:\n'
-        'dart devtools --appSizeBase=$relativeAppSizePath'
+        'dart devtools --appSizeBase=${outputFile.path}'
       );
     }
 

packages/flutter_tools/lib/src/linux/build_linux.dart

@@ -124,11 +124,9 @@ Future<void> buildLinux(
       'A summary of your Linux bundle analysis can be found at: ${outputFile.path}',
     );
 
-    // DevTools expects a file path relative to the .flutter-devtools/ dir.
-    final String relativeAppSizePath = outputFile.path.split('.flutter-devtools/').last.trim();
     logger.printStatus(
       '\nTo analyze your app size in Dart DevTools, run the following command:\n'
-      'dart devtools --appSizeBase=$relativeAppSizePath'
+      'dart devtools --appSizeBase=${outputFile.path}'
     );
   }
 }

packages/flutter_tools/lib/src/macos/build_macos.dart

@@ -303,11 +303,9 @@ Future<void> _writeCodeSizeAnalysis(BuildInfo buildInfo, SizeAnalyzer? sizeAnaly
     'A summary of your macOS bundle analysis can be found at: ${outputFile.path}',
   );
 
-  // DevTools expects a file path relative to the .flutter-devtools/ dir.
-  final String relativeAppSizePath = outputFile.path.split('.flutter-devtools/').last.trim();
   globals.printStatus(
     '\nTo analyze your app size in Dart DevTools, run the following command:\n'
-    'dart devtools --appSizeBase=$relativeAppSizePath'
+    'dart devtools --appSizeBase=${outputFile.path}'
   );
 }
 

packages/flutter_tools/lib/src/windows/build_windows.dart

@@ -157,11 +157,9 @@ Future<void> buildWindows(
       'A summary of your Windows bundle analysis can be found at: ${outputFile.path}',
     );
 
-    // DevTools expects a file path relative to the .flutter-devtools/ dir.
-    final String relativeAppSizePath = outputFile.path.split('.flutter-devtools/').last.trim();
     globals.printStatus(
       '\nTo analyze your app size in Dart DevTools, run the following command:\n'
-      'dart devtools --appSizeBase=$relativeAppSizePath'
+      'dart devtools --appSizeBase=${outputFile.path}'
     );
   }
 }

packages/flutter_tools/test/integration.shard/analyze_size_test.dart

@@ -46,8 +46,7 @@ void main() {
         .split('\n')
         .firstWhere((String line) => line.contains(runDevToolsMessage));
     final String commandArguments = devToolsCommand.split(runDevToolsMessage).last.trim();
-    final String relativeAppSizePath = outputFilePath.split('.flutter-devtools/').last.trim();
-    expect(commandArguments.contains('--appSizeBase=$relativeAppSizePath'), isTrue);
+    expect(commandArguments.contains('--appSizeBase=$outputFilePath'), isTrue);
   });
 
   testWithoutContext('--analyze-size flag produces expected output on hello_world for iOS', () async {
@@ -80,9 +79,8 @@ void main() {
         .split('\n')
         .firstWhere((String line) => line.contains(runDevToolsMessage));
     final String commandArguments = devToolsCommand.split(runDevToolsMessage).last.trim();
-    final String relativeAppSizePath = outputFilePath.split('.flutter-devtools/').last.trim();
 
-    expect(commandArguments.contains('--appSizeBase=$relativeAppSizePath'), isTrue);
+    expect(commandArguments.contains('--appSizeBase=$outputFilePath'), isTrue);
     expect(codeSizeDir.existsSync(), true);
     tempDir.deleteSync(recursive: true);
   }, skip: !platform.isMacOS); // [intended] iOS can only be built on macos.
@@ -132,9 +130,8 @@ void main() {
         .split('\n')
         .firstWhere((String line) => line.contains(runDevToolsMessage));
     final String commandArguments = devToolsCommand.split(runDevToolsMessage).last.trim();
-    final String relativeAppSizePath = outputFilePath.split('.flutter-devtools/').last.trim();
 
-    expect(commandArguments.contains('--appSizeBase=$relativeAppSizePath'), isTrue);
+    expect(commandArguments.contains('--appSizeBase=$outputFilePath'), isTrue);
     expect(codeSizeDir.existsSync(), true);
     tempDir.deleteSync(recursive: true);
   }, skip: !platform.isMacOS); // [intended] this is a macos only test.