Disable RAW test on Chrome OS, Windows

TBR=scroggo@google.com

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1633763002

Review URL: https://codereview.chromium.org/1633763002
diff --git a/tests/CodexTest.cpp b/tests/CodexTest.cpp
index 5210cf4..11d02cd 100644
--- a/tests/CodexTest.cpp
+++ b/tests/CodexTest.cpp
@@ -452,7 +452,9 @@
     check(r, "yellow_rose.png", SkISize::Make(400, 301), true, false, false);
 
     // RAW
+#if defined(SK_CODEC_DECODES_RAW)
     check(r, "sample_1mp.dng", SkISize::Make(600, 338), false, false, false);
+#endif
 }
 
 // Test interlaced PNG in stripes, similar to DM's kStripe_Mode