Tracking uniform ownership

This is a prerequisite change for the upcoming sample(child, matrix)
function. By itself, this CL doesn't really change anything; it just
adds an ownership tracking feature which sample(child, matrix) depends
on.

Change-Id: I98b12e5fb062a2535af367931e7a932ea9c63a59
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/281337
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
diff --git a/src/gpu/ccpr/GrCCPathProcessor.cpp b/src/gpu/ccpr/GrCCPathProcessor.cpp
index ca34af6..d4c1d8b 100644
--- a/src/gpu/ccpr/GrCCPathProcessor.cpp
+++ b/src/gpu/ccpr/GrCCPathProcessor.cpp
@@ -158,7 +158,7 @@
 
     const char* atlasAdjust;
     fAtlasAdjustUniform = uniHandler->addUniform(
-            kVertex_GrShaderFlag, kFloat2_GrSLType, "atlas_adjust", &atlasAdjust);
+            nullptr, kVertex_GrShaderFlag, kFloat2_GrSLType, "atlas_adjust", &atlasAdjust);
 
     varyingHandler->emitAttributes(proc);