Fix generic color space xform, ColorSpaceXformTest

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2275563002

Review-Url: https://codereview.chromium.org/2275563002
diff --git a/tests/ColorSpaceXformTest.cpp b/tests/ColorSpaceXformTest.cpp
index 464801a..415063d 100644
--- a/tests/ColorSpaceXformTest.cpp
+++ b/tests/ColorSpaceXformTest.cpp
@@ -19,7 +19,9 @@
         // Logically we can pass any matrix here.  For simplicty, pass I(), i.e. D50 XYZ gamut.
         sk_sp<SkColorSpace> space(new SkColorSpace_Base(
                 nullptr, SkColorSpace::kNonStandard_GammaNamed, gammas, SkMatrix::I(), nullptr));
-        return SkColorSpaceXform::New(space, space);
+
+        // Use special testing entry point, so we don't skip the xform, even though src == dst.
+        return SlowIdentityXform(space);
     }
 };
 
@@ -37,19 +39,19 @@
 
     // Create and perform an identity xform.
     std::unique_ptr<SkColorSpaceXform> xform = ColorSpaceXformTest::CreateIdentityXform(gammas);
-    xform->apply(dstPixels, srcPixels, width, kRGBA_8888_SkColorType, kOpaque_SkAlphaType);
+    xform->apply(dstPixels, srcPixels, width, kN32_SkColorType, kOpaque_SkAlphaType);
 
     // Since the src->dst matrix is the identity, and the gamma curves match,
     // the pixels should be unchanged.
     for (int i = 0; i < width; i++) {
         REPORTER_ASSERT(r, almost_equal(((srcPixels[i] >>  0) & 0xFF),
-                                        ((dstPixels[i] >>  0) & 0xFF)));
+                                        SkGetPackedR32(dstPixels[i])));
         REPORTER_ASSERT(r, almost_equal(((srcPixels[i] >>  8) & 0xFF),
-                                        ((dstPixels[i] >>  8) & 0xFF)));
+                                        SkGetPackedG32(dstPixels[i])));
         REPORTER_ASSERT(r, almost_equal(((srcPixels[i] >> 16) & 0xFF),
-                                        ((dstPixels[i] >> 16) & 0xFF)));
+                                        SkGetPackedB32(dstPixels[i])));
         REPORTER_ASSERT(r, almost_equal(((srcPixels[i] >> 24) & 0xFF),
-                                        ((dstPixels[i] >> 24) & 0xFF)));
+                                        SkGetPackedA32(dstPixels[i])));
     }
 }