Make sure to visit clips and dst proxies during gather

Bug: skia:7190
Change-Id: I0cd4f7734047550c7904f44892ef266498842e0c
Reviewed-on: https://skia-review.googlesource.com/77940
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
diff --git a/src/gpu/GrRenderTargetOpList.h b/src/gpu/GrRenderTargetOpList.h
index e9797db..7e600d4 100644
--- a/src/gpu/GrRenderTargetOpList.h
+++ b/src/gpu/GrRenderTargetOpList.h
@@ -136,6 +136,19 @@
                 fDstProxy = *dstProxy;
             }
         }
+
+        void visitProxies(const GrOp::VisitProxyFunc& func) const {
+            if (fOp) {
+                fOp->visitProxies(func);
+            }
+            if (fDstProxy.proxy()) {
+                func(fDstProxy.proxy());
+            }
+            if (fAppliedClip) {
+                fAppliedClip->visitProxies(func);
+            }
+        }
+
         std::unique_ptr<GrOp> fOp;
         DstProxy fDstProxy;
         GrAppliedClip* fAppliedClip;