Move internal calls from GrContext to GrContextPriv

A mechanical bulk move just to get these out of the public API.

TBR=bsalomon@google.com
Change-Id: I813efbd54a09dd448275697c0e50947753a5cfd3
Reviewed-on: https://skia-review.googlesource.com/112262
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
diff --git a/tests/GrMeshTest.cpp b/tests/GrMeshTest.cpp
index acac61b..80788dd 100644
--- a/tests/GrMeshTest.cpp
+++ b/tests/GrMeshTest.cpp
@@ -82,8 +82,8 @@
 DEF_GPUTEST_FOR_RENDERING_CONTEXTS(GrMeshTest, reporter, ctxInfo) {
     GrContext* const context = ctxInfo.grContext();
 
-    sk_sp<GrRenderTargetContext> rtc(
-        context->makeDeferredRenderTargetContext(SkBackingFit::kExact, kImageWidth, kImageHeight,
+    sk_sp<GrRenderTargetContext> rtc(context->contextPriv().makeDeferredRenderTargetContext(
+                                                 SkBackingFit::kExact, kImageWidth, kImageHeight,
                                                  kRGBA_8888_GrPixelConfig, nullptr));
     if (!rtc) {
         ERRORF(reporter, "could not create render target context.");