Move resourceProvider accessor to GrContextPriv (take 2)

TBR=bsalomon@google.com
Change-Id: I3fd46ebfad0d04b8a2bfa6190f81308f3a6be620
Reviewed-on: https://skia-review.googlesource.com/95121
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
diff --git a/tests/WritePixelsTest.cpp b/tests/WritePixelsTest.cpp
index b3da67b..a41e8f4 100644
--- a/tests/WritePixelsTest.cpp
+++ b/tests/WritePixelsTest.cpp
@@ -504,7 +504,7 @@
 
         sk_sp<GrTextureProxy> temp = proxyProvider->createProxy(desc, SkBackingFit::kApprox,
                                                                 SkBudgeted::kYes);
-        temp->instantiate(context->resourceProvider());
+        temp->instantiate(context->contextPriv().resourceProvider());
     }
 
     // Create the surfaces and flush them to ensure there is no lingering pendingIO