Update various flutter.dev links to more stable destinations

Bug: https://github.com/flutter/website/issues/10363
CoreLibraryReviewExempt: Just updating link in API doc.
Change-Id: I6c4dc17206410fa86e88b4630c8056a994e18967
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/372381
Reviewed-by: Devon Carew <devoncarew@google.com>
Commit-Queue: Devon Carew <devoncarew@google.com>
Reviewed-by: Sam Rawlins <srawlins@google.com>
Auto-Submit: Parker Lougheed <parlough@gmail.com>

docs/gsoc/Dart-GSoC-2020-Project-Ideas.md

@@ -234,7 +234,7 @@ application](https://github.com/flutter/flutter/issues/23794), which would invol
 an audio player plugin for both Android and iOS in addition to a UI in Flutter.
 
 **Getting Started**:
-Create a simple Flutter application which utilizes method channels to invoke functionality written in native code via Dart (Java or Kotlin for Android, Objective-C or Swift for iOS). This doesn't have to be anything complicated, just enough to experiment with writing code that crosses language boundaries. See Flutter documentation on [developing packages and plugins](https://flutter.dev/docs/development/packages-and-plugins/developing-packages) for information needed to get started.
+Create a simple Flutter application which utilizes method channels to invoke functionality written in native code via Dart (Java or Kotlin for Android, Objective-C or Swift for iOS). This doesn't have to be anything complicated, just enough to experiment with writing code that crosses language boundaries. See Flutter documentation on [developing packages and plugins](https://flutter.dev/to/develop-packages) for information needed to get started.
 
 It's also recommended that you read through the article on [background execution in Flutter](https://medium.com/flutter/executing-dart-in-the-background-with-flutter-plugins-and-geofencing-2b3e40a1a124). While this is slightly out of date, the general concepts are still correct and will be important for this project.
 

docs/gsoc/Dart-GSoC-2023-Project-Ideas.md

@@ -146,7 +146,7 @@ A good project proposal will describe what Java APIs are necessary to implement
 
 We would like to explore the possibilities of the new language features that could help to improve packages and create a new API (potentially) or refactor internal coding that make the package to take full advantage of Dart 3. We would like to also prepare a guideline after this refactoring for other maintainers to figure out what could be improved or changed.
 
-We are using [Federated plugins](https://docs.flutter.dev/development/packages-and-plugins/developing-packages#federated-plugins)  therefore this is likely to involve:
+We are using [Federated plugins](https://flutter.dev/to/federated-plugins), therefore this is likely to involve:
  
 * refactoring `platform_interface` class for each package,
 * refactoring app-facing and platform-specific-implementation packages,

pkg/analyzer/lib/src/wolf/README.md

@@ -43,7 +43,7 @@ The design consists of multiple analysis stages:
 
 - AST-to-IR. The analyzer's AST is converted to a stack-based IR (intermediate
   representation). The proposed IR and the approach for converting to it are
-  described in http://flutter.dev/go/dart-static-analysis-ir.
+  described in https://flutter.dev/go/dart-static-analysis-ir.
 
 - Scope analysis. A pass is made through the IR, identifying all the state
   variables of interest. This includes local variables as well as any other

pkg/analyzer/tool/diagnostics/diagnostics.md

@@ -24997,7 +24997,7 @@ flutter:
         fileName: hello_web.dart
 ```
 
-See [Developing packages & plugins](https://docs.flutter.dev/packages-and-plugins/developing-packages)
+See [Developing packages & plugins](https://flutter.dev/to/develop-packages)
 for more information.
 
 ### await_only_futures

pkg/dartdev/lib/src/templates/package.dart

@@ -73,12 +73,12 @@ This README describes the package. If you publish this package to pub.dev,
 this README's contents appear on the landing page for your package.
 
 For information about how to write a good package README, see the guide for
-[writing package pages](https://dart.dev/guides/libraries/writing-package-pages). 
+[writing package pages](https://dart.dev/tools/pub/writing-package-pages). 
 
 For general information about developing packages, see the Dart guide for
-[creating packages](https://dart.dev/guides/libraries/create-library-packages)
+[creating packages](https://dart.dev/guides/libraries/create-packages)
 and the Flutter guide for
-[developing packages and plugins](https://flutter.dev/developing-packages). 
+[developing packages and plugins](https://flutter.dev/to/develop-packages). 
 -->
 
 TODO: Put a short description of the package here that helps potential users

pkg/linter/README.md

@@ -84,7 +84,7 @@ Please file feature requests and bugs in the [issue tracker][tracker].
 [dart_cli]: https://dart.dev/tools/dart-tool
 [effective_dart]: https://dart.dev/effective-dart
 [lints]: https://dart.dev/lints
-[options_file]: https://dart.dev/guides/language/analysis-options#the-analysis-options-file
+[options_file]: https://dart.dev/tools/analysis#the-analysis-options-file
 [package-dart-lints]: https://github.com/dart-lang/lints
 [package-flutter-lints]: https://github.com/flutter/packages/tree/main/packages/flutter_lints
 [style_guide]: https://dart.dev/effective-dart/style

pkg/linter/messages.yaml

@@ -729,7 +729,7 @@ LintCode:
               fileName: hello_web.dart
       ```
 
-      See [Developing packages & plugins](https://docs.flutter.dev/packages-and-plugins/developing-packages)
+      See [Developing packages & plugins](https://flutter.dev/to/develop-packages)
       for more information.
   await_only_futures:
     documentation: |-

sdk/lib/developer/profiler.dart

@@ -5,7 +5,7 @@
 part of dart.developer;
 
 /// A UserTag can be used to group samples in the
-/// [DevTools CPU profiler](https://flutter.dev/docs/development/tools/devtools/cpu-profiler).
+/// [DevTools CPU profiler](https://docs.flutter.dev/tools/devtools/cpu-profiler).
 abstract final class UserTag {
   /// The maximum number of UserTag instances that can be created by a program.
   static const maxUserTags = 64;