Add a single MacOS+Vulkan+SwiftShader CI test

impeller/playground/backend/vulkan/playground_impl_vk.cc

@@ -93,6 +93,15 @@ PlaygroundImplVK::PlaygroundImplVK(PlaygroundSwitches switches)
     return;
   }
 
+  // Without this, the playground will timeout waiting for the presentation.
+  // It's better to have some Vulkan validation tests running on CI to catch
+  // regressions, but for now this is a workaround.
+  //
+  // TODO(matanlurey): https://github.com/flutter/flutter/issues/134852.
+  //
+  // (Note, if you're using MoltenVK, or Linux, you can comment out this line).
+  context_vk->SetSyncPresentation(true);
+
   VkSurfaceKHR vk_surface;
   auto res = vk::Result{::glfwCreateWindowSurface(
       context_vk->GetInstance(),  // instance

testing/run_tests.py

@@ -516,14 +516,33 @@ def make_test(name, flags=None, extra_env=None):
         shuffle_flags + ['--enable_vulkan_validation'],
         coverage=coverage,
         extra_env=extra_env,
-        # TODO(117122): Remove this allowlist.
-        # https://github.com/flutter/flutter/issues/114872
+        # TODO(https://github.com/flutter/flutter/issues/123733): Remove this allowlist.
+        # See also https://github.com/flutter/flutter/issues/114872.
         allowed_failure_output=[
             '[MTLCompiler createVertexStageAndLinkPipelineWithFragment:',
             '[MTLCompiler pipelineStateWithVariant:',
         ]
     )
 
+    # Run one interactive Vulkan test with validation enabled.
+    #
+    # TODO(matanlurey): https://github.com/flutter/flutter/issues/134852; enable
+    # more of the suite, and ideally we'd like to use Skia gold and take screen
+    # shots as well.
+    run_engine_executable(
+        build_dir,
+        'impeller_unittests',
+        executable_filter,
+        shuffle_flags + [
+            '--enable_vulkan_validation',
+            '--enable_playground',
+            '--playground_timeout_ms=4000',
+            '--gtest_filter="*ColorWheel/Vulkan"',
+        ],
+        coverage=coverage,
+        extra_env=extra_env,
+    )
+
 
 def run_engine_benchmarks(build_dir, executable_filter):
   logger.info('Running Engine Benchmarks.')