Add guards for upcoming Skia changes

https://skia-review.googlesource.com/c/skia/+/160481 and
https://skia-review.googlesource.com/c/skia/+/163520

Change-Id: Icade482f7a82fb4661f76486bc2c85af5abe7dfe
Reviewed-on: https://chromium-review.googlesource.com/c/1288853
Commit-Queue: Mike Klein <mtklein@chromium.org>
Reviewed-by: Mike Klein <mtklein@chromium.org>
Cr-Commit-Position: refs/heads/master@{#601113}

skia/config/SkUserConfig.h

@@ -154,10 +154,14 @@ SK_API void SkDebugf_FileLine(const char* file, int line, bool fatal,
 // Max. verb count for paths rendered by the edge-AA tessellating path renderer.
 #define GR_AA_TESSELLATOR_MAX_VERB_COUNT 100
 
+#define SK_LEGACY_COMPLEX_XFERMODES
+
 #ifndef SK_SUPPORT_LEGACY_AAA_CHOICE
 #define SK_SUPPORT_LEGACY_AAA_CHOICE
 #endif
 
+#define SK_USE_LEGACY_LAZY_IMAGE_DECODE
+
 ///////////////////////// Imported from BUILD.gn and skia_common.gypi
 
 /* In some places Skia can use static initializers for global initialization,