Finish overriding onMakeColorSpace() for SkImageFilters

Fixes 3 gms in gbr-8888.  Breaks 0 gms in gbr-8888.

Bug: skia:
Change-Id: I3365390b16353821ef6057a7bb68020887e36f72
Reviewed-on: https://skia-review.googlesource.com/13323
Commit-Queue: Matt Sarett <msarett@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>
diff --git a/tests/ImageFilterTest.cpp b/tests/ImageFilterTest.cpp
index 5d959d1..56cd5d5 100644
--- a/tests/ImageFilterTest.cpp
+++ b/tests/ImageFilterTest.cpp
@@ -63,6 +63,9 @@
         offset->fX = offset->fY = 0;
         return sk_ref_sp<SkSpecialImage>(source);
     }
+    sk_sp<SkImageFilter> onMakeColorSpace(SkColorSpaceXformer*) const override {
+        return sk_ref_sp(const_cast<MatrixTestImageFilter*>(this));
+    }
 
     void flatten(SkWriteBuffer& buffer) const override {
         SkDEBUGFAIL("Should never get here");
@@ -90,6 +93,9 @@
                                         SkIPoint* offset) const override {
         return nullptr;
     }
+    sk_sp<SkImageFilter> onMakeColorSpace(SkColorSpaceXformer*) const override {
+        return nullptr;
+    }
 
     SK_TO_STRING_OVERRIDE()
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(FailImageFilter)