Move explicit backend object allocation API to GrContext

This initial portion of the API should be ready to go. Follow on CLs will add the other entry points.

Change-Id: Ia9c708046ba08b16f9a71558e2bf2c38279abe5d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/214680
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
diff --git a/tools/gpu/ProxyUtils.cpp b/tools/gpu/ProxyUtils.cpp
index 9e01b17..d3cc1f1 100644
--- a/tools/gpu/ProxyUtils.cpp
+++ b/tools/gpu/ProxyUtils.cpp
@@ -34,7 +34,7 @@
     sk_sp<GrTextureProxy> proxy;
     if (kBottomLeft_GrSurfaceOrigin == origin) {
         // We (soon will) only support using kBottomLeft with wrapped textures.
-        auto backendTex = context->priv().createBackendTexture(
+        auto backendTex = context->createBackendTexture(
                 width, height, format, GrMipMapped::kNo, renderable);
         if (!backendTex.isValid()) {
             return nullptr;
@@ -51,7 +51,7 @@
         }
 
         if (!proxy) {
-            context->priv().deleteBackendTexture(backendTex);
+            context->deleteBackendTexture(backendTex);
             return nullptr;
         }