Add empty analyzer_testing package

Work towards https://github.com/dart-lang/sdk/issues/55660

Change-Id: Ia4f8186c328c9929869d1305ee0fe606d9dfa0e5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/425320
Commit-Queue: Samuel Rawlins <srawlins@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Reviewed-by: Alexander Thomas <athom@google.com>

pkg/analyzer_testing/LICENSE

@@ -0,0 +1,26 @@
+Copyright 2012, the Dart project authors.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+    * Neither the name of Google LLC nor the names of its
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

pkg/analyzer_testing/README.md

@@ -0,0 +1,21 @@
+This package provides testing utilities related to the [analyzer][] and
+[analysis_server_plugin][] packages.
+
+## Support
+
+Post issues and feature requests at https://github.com/dart-lang/sdk/issues.
+These will be triaged according to the [analyzer triage priorities][triage].
+
+Questions and discussions are welcome at the
+[#hackers-analyzer Discord channel][discord channel].
+
+## License
+
+See the [LICENSE] file.
+
+[analyzer]: https://pub.dev/packages/analyzer
+[analysis_server_plugin: https://pub.dev/packages/analysis_server_plugin
+[discored channel]: https://discord.com/channels/608014603317936148/1171510601655275612
+[LICENSE]: https://github.com/dart-lang/sdk/blob/main/pkg/analyzer/LICENSE
+[triage]: https://github.com/dart-lang/sdk/blob/main/pkg/analyzer/TRIAGE.md
+

pkg/analyzer_testing/pubspec.yaml

@@ -0,0 +1,6 @@
+name: analyzer_testing
+
+environment:
+  sdk: ^3.7.0
+
+resolution: workspace

pubspec.yaml

@@ -21,6 +21,7 @@ workspace:
   - pkg/analyzer
   - pkg/analyzer_cli
   - pkg/analyzer_plugin
+  - pkg/analyzer_testing
   - pkg/analyzer_utilities
   - pkg/async_helper
   - pkg/bisect_dart