[Impeller] added test for bgra10xr png encoding (flutter#53182)

fixes: flutter/flutter#148851
depends on: 
 - https://skia-review.googlesource.com/c/skcms/+/861638
 - https://skia-review.googlesource.com/c/skia/+/861516

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Author: gaaclarke

lib/ui/painting/image_encoding_unittests.cc

@@ -469,6 +469,28 @@ TEST(ImageEncodingImpellerTest, PngEncoding10XR) {
   EXPECT_TRUE(png.ok());
 }
 
+TEST(ImageEncodingImpellerTest, PngEncodingBGRA10XR) {
+  int width = 100;
+  int height = 100;
+  SkImageInfo info = SkImageInfo::Make(
+      width, height, kBGRA_10101010_XR_SkColorType, kUnpremul_SkAlphaType);
+
+  auto surface = SkSurfaces::Raster(info);
+  SkCanvas* canvas = surface->getCanvas();
+
+  SkPaint paint;
+  paint.setColor(SK_ColorBLUE);
+  paint.setAntiAlias(true);
+
+  canvas->clear(SK_ColorWHITE);
+  canvas->drawCircle(width / 2, height / 2, 100, paint);
+
+  sk_sp<SkImage> image = surface->makeImageSnapshot();
+
+  fml::StatusOr<sk_sp<SkData>> png = EncodeImage(image, ImageByteFormat::kPNG);
+  EXPECT_TRUE(png.ok());
+}
+
 #endif  // IMPELLER_SUPPORTS_RENDERING
 
 }  // namespace testing