Add Gr*Proxy classes

This isn't wired in anywhere yet.

GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1937553002

Committed: https://skia.googlesource.com/skia/+/de5bf0cfeca908b81a28cc50065f7bc2da3d2fd1

Review-Url: https://codereview.chromium.org/1937553002
diff --git a/tests/PrimitiveProcessorTest.cpp b/tests/PrimitiveProcessorTest.cpp
index b1157a3..a82237d 100644
--- a/tests/PrimitiveProcessorTest.cpp
+++ b/tests/PrimitiveProcessorTest.cpp
@@ -104,7 +104,7 @@
 DEF_GPUTEST_FOR_ALL_GL_CONTEXTS(VertexAttributeCount, reporter, ctxInfo) {
     GrContext* context = ctxInfo.fGrContext;
 
-    sk_sp<GrDrawContext> dc(context->newDrawContext(GrContext::kLoose_BackingFit,
+    sk_sp<GrDrawContext> dc(context->newDrawContext(SkBackingFit::kApprox,
                                                     1, 1, kRGBA_8888_GrPixelConfig));
     if (!dc) {
         ERRORF(reporter, "Could not create draw context.");