Adds vscode workspace with impeller test runner (#55291)

This PR removes our checked in .vscode files and instead starts a vscode
workspace for the engine. As a first step I've added build tasks for the
arm64 `impeller_unittests`. I also setup C++ TestMate so that we can
easily navigate to tests and execute them. The tests will be rebuilt
before each execution.

The goal would be that eventually all of our c++ tests can be listed
here. This is going to make external contribution much easier and make
it so I don't have to keep editing the "launch.json" file to run
specific tests.


![ezgif-2-bcd582b44e](https://github.com/user-attachments/assets/11cea32e-628f-4626-b87d-9d3ebfe11357)

## 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] and the [C++,
Objective-C, Java style guides].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I added new tests to check the change I am making or feature I am
adding, or the PR is [test-exempt]. See [testing the engine] for
instructions on writing and running engine tests.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I signed the [CLA].
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#overview
[Tree Hygiene]: https://github.com/flutter/flutter/wiki/Tree-hygiene
[test-exempt]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#tests
[Flutter Style Guide]:
https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo
[C++, Objective-C, Java style guides]:
https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#style
[testing the engine]:
https://github.com/flutter/flutter/wiki/Testing-the-engine
[CLA]: https://cla.developers.google.com/
[flutter/tests]: https://github.com/flutter/tests
[breaking change policy]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#handling-breaking-changes
[Discord]: https://github.com/flutter/flutter/wiki/Chat

Author: gaaclarke

.gitignore

@@ -49,7 +49,6 @@ xcuserdata
 .project
 .settings/
 .vscode/
-!.vscode/extensions.json
 
 # packages file containing multi-root paths
 .packages.generated

.vscode/extensions.json

@@ -18,7 +18,6 @@
 ../../../flutter/.github
 ../../../flutter/.gitignore
 ../../../flutter/.style.yapf
-../../../flutter/.vscode
 ../../../flutter/AUTHORS
 ../../../flutter/CODEOWNERS
 ../../../flutter/CONTRIBUTING.md
@@ -50,6 +49,7 @@
 ../../../flutter/display_list/utils/dl_accumulation_rect_unittests.cc
 ../../../flutter/display_list/utils/dl_matrix_clip_tracker_unittests.cc
 ../../../flutter/docs
+../../../flutter/engine.code-workspace
 ../../../flutter/examples
 ../../../flutter/flow/README.md
 ../../../flutter/flow/diff_context_unittests.cc

ci/licenses_golden/excluded_files

@@ -1,2 +1,2 @@
-Signature: 53025d1261891c38c7bccb158862e09f
+Signature: 8859e172e060ecb45aa665c3119d5d25
 

ci/licenses_golden/tool_signature

@@ -0,0 +1,258 @@
+{
+  "folders": [
+    {
+      "path": "."
+    }
+  ],
+  "settings": {
+    "files.associations": {
+      "optional": "cpp",
+      "__bit_reference": "cpp",
+      "__bits": "cpp",
+      "__config": "cpp",
+      "__debug": "cpp",
+      "__errc": "cpp",
+      "__hash_table": "cpp",
+      "__locale": "cpp",
+      "__mutex_base": "cpp",
+      "__node_handle": "cpp",
+      "__nullptr": "cpp",
+      "__split_buffer": "cpp",
+      "__string": "cpp",
+      "__threading_support": "cpp",
+      "__tree": "cpp",
+      "__tuple": "cpp",
+      "any": "cpp",
+      "array": "cpp",
+      "atomic": "cpp",
+      "bitset": "cpp",
+      "cctype": "cpp",
+      "chrono": "cpp",
+      "cinttypes": "cpp",
+      "clocale": "cpp",
+      "cmath": "cpp",
+      "codecvt": "cpp",
+      "compare": "cpp",
+      "complex": "cpp",
+      "concepts": "cpp",
+      "condition_variable": "cpp",
+      "csignal": "cpp",
+      "cstdarg": "cpp",
+      "cstddef": "cpp",
+      "cstdint": "cpp",
+      "cstdio": "cpp",
+      "cstdlib": "cpp",
+      "cstring": "cpp",
+      "ctime": "cpp",
+      "cwchar": "cpp",
+      "cwctype": "cpp",
+      "deque": "cpp",
+      "exception": "cpp",
+      "forward_list": "cpp",
+      "fstream": "cpp",
+      "future": "cpp",
+      "initializer_list": "cpp",
+      "iomanip": "cpp",
+      "ios": "cpp",
+      "iosfwd": "cpp",
+      "iostream": "cpp",
+      "istream": "cpp",
+      "limits": "cpp",
+      "list": "cpp",
+      "locale": "cpp",
+      "map": "cpp",
+      "memory": "cpp",
+      "mutex": "cpp",
+      "new": "cpp",
+      "numeric": "cpp",
+      "ostream": "cpp",
+      "queue": "cpp",
+      "random": "cpp",
+      "ratio": "cpp",
+      "regex": "cpp",
+      "set": "cpp",
+      "span": "cpp",
+      "sstream": "cpp",
+      "stack": "cpp",
+      "stdexcept": "cpp",
+      "streambuf": "cpp",
+      "string": "cpp",
+      "string_view": "cpp",
+      "strstream": "cpp",
+      "system_error": "cpp",
+      "tuple": "cpp",
+      "type_traits": "cpp",
+      "typeinfo": "cpp",
+      "unordered_map": "cpp",
+      "unordered_set": "cpp",
+      "valarray": "cpp",
+      "variant": "cpp",
+      "vector": "cpp",
+      "algorithm": "cpp",
+      "filesystem": "cpp",
+      "memory_resource": "cpp",
+      "bit": "cpp",
+      "charconv": "cpp",
+      "format": "cpp",
+      "functional": "cpp",
+      "iterator": "cpp",
+      "utility": "cpp",
+      "__assert": "cpp",
+      "*.inc": "cpp",
+      "__verbose_abort": "cpp",
+      "*.def": "cpp",
+      "*.hpp11": "cpp",
+      "__functional_base": "cpp",
+      "shared_mutex": "cpp",
+      "coroutine": "cpp",
+      "hash_map": "cpp",
+      "hash_set": "cpp",
+      "thread": "cpp",
+      "propagate_const": "cpp",
+      "*.gen": "cpp",
+      "simd": "cpp",
+      "barrier": "cpp",
+      "cuchar": "cpp",
+      "latch": "cpp",
+      "numbers": "cpp",
+      "scoped_allocator": "cpp",
+      "semaphore": "cpp",
+      "typeindex": "cpp",
+      "__std_stream": "cpp",
+      "*.ipp": "cpp",
+      "csetjmp": "cpp",
+      "cfenv": "cpp"
+    },
+    "C_Cpp.default.includePath": [
+      "${default}",
+      "${workspaceFolder}/..",
+      "${workspaceFolder}",
+    ],
+    "dotnet.defaultSolution": "disable",
+    "dart.showTodos": false,
+    "testMate.cpp.test.advancedExecutables": [
+      {
+        "name": "impeller_unittests_arm64",
+        "pattern": "../out/host_debug_unopt_arm64/impeller_unittests",
+        "runTask": {
+          "before": [
+            "impeller_unittests_arm64"
+          ]
+        },
+        "gtest": {
+          "prependTestRunningArgs": [
+            "--enable_playground"
+          ]
+        }
+      }
+    ],
+    "testMate.cpp.debug.configTemplate": {
+      "type": "cppvsdbg",
+      "linux": {
+        "type": "cppdbg",
+        "MIMode": "gdb"
+      },
+      "darwin": {
+        "type": "cppdbg",
+        "MIMode": "lldb",
+        "setupCommands": [
+          {
+            "description": "Source map",
+            "text": "settings set target.source-map \"flutter/\" \"${workspaceFolder}\"",
+            "ignoreFailures": false
+          }
+        ],
+      },
+      "win32": {
+        "type": "cppvsdbg"
+      },
+      "program": "${exec}",
+      "args": "${argsArray}",
+      "cwd": "${cwd}",
+      "env": "${envObj}",
+      "environment": "${envObjArray}",
+      "sourceFileMap": "${sourceFileMapObj}",
+    }
+  },
+  "tasks": {
+    "version": "2.0.0",
+    "tasks": [
+      {
+        "label": "impeller_unittests_arm64",
+        "type": "shell",
+        "command": "./flutter/bin/et",
+        "args": [
+          "build",
+          "-c",
+          "host_debug_unopt_arm64",
+          "//flutter/impeller:impeller_unittests"
+        ],
+        "options": {
+          "cwd": "${workspaceFolder}/.."
+        },
+        "problemMatcher": [
+          "$gcc"
+        ],
+        "presentation": {
+          "echo": true,
+          "reveal": "always",
+          "focus": false,
+          "panel": "shared",
+          "clear": true
+        },
+        "group": {
+          "kind": "build",
+        }
+      }
+    ]
+  },
+  "extensions": {
+    "recommendations": [
+      // C++ TestMate
+      "matepek.vscode-catch2-test-adapter",
+      // Uses github-styled markdown preview, which supports more features than the default markdown preview.
+      "bierner.github-markdown-preview",
+      // Flutter and Dart extensions.
+      "Dart-Code.dart-code",
+      // Supports C/C++ in the engine.
+      // See https://github.com/flutter/engine/blob/main/docs/contributing/Setting-up-the-Engine-development-environment.md#vscode-with-cc-intellisense-cc
+      "llvm-vs-code-extensions.vscode-clangd",
+      // Auto-formats C/C++ code.
+      // https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#cc
+      "xaver.clang-format",
+    ]
+  },
+  "launch": {
+    "version": "0.2.0",
+    "configurations": [
+      {
+        "name": "impeller_unittests_arm64",
+        "type": "cppdbg",
+        "request": "launch",
+        "program": "${workspaceFolder}/../out/host_debug_unopt_arm64/impeller_unittests",
+        "args": [
+          "--enable_playground",
+        ],
+        "stopAtEntry": false,
+        "cwd": "${workspaceFolder}/../out/host_debug_unopt_arm64",
+        "environment": [],
+        "externalConsole": false,
+        "MIMode": "lldb",
+        "setupCommands": [
+          {
+            "description": "Enable pretty-printing for lldb",
+            "text": "settings set target.pretty-printing true",
+            "ignoreFailures": true
+          },
+          {
+            "description": "Source map",
+            "text": "settings set target.source-map \"flutter/\" \"${workspaceFolder}\"",
+            "ignoreFailures": false
+          }
+        ],
+        "preLaunchTask": "impeller_unittests_arm64",
+      }
+    ],
+    "compounds": []
+  }
+}

engine.code-workspace

@@ -25,6 +25,7 @@ final Set<String> skippedPaths = <String>{
   r'flutter/buildtools', // only used by build
   r'flutter/ci',
   r'flutter/docs',
+  r'flutter/engine.code-workspace',
   r'flutter/flutter_frontend_server',
   r'flutter/impeller/docs',
   r'flutter/lib/web_ui/build', // this is compiler-generated output