Make GrCaps and GrShaderCaps private.

Moves getCaps() from GrContext to GrContextPriv and removes unused refCaps().

Change-Id: Ic6a8951b656c0d1b2773eae73bff8e88af819866
Reviewed-on: https://skia-review.googlesource.com/127389
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
diff --git a/src/gpu/GrDrawOpTest.cpp b/src/gpu/GrDrawOpTest.cpp
index 7aba424..d14e5b5 100644
--- a/src/gpu/GrDrawOpTest.cpp
+++ b/src/gpu/GrDrawOpTest.cpp
@@ -8,6 +8,7 @@
 #include "GrDrawOpTest.h"
 #include "GrCaps.h"
 #include "GrContext.h"
+#include "GrContextPriv.h"
 #include "GrUserStencilSettings.h"
 #include "SkRandom.h"
 #include "SkTypes.h"
@@ -15,7 +16,7 @@
 #if GR_TEST_UTILS
 
 const GrUserStencilSettings* GrGetRandomStencil(SkRandom* random, GrContext* context) {
-    if (context->caps()->avoidStencilBuffers()) {
+    if (context->contextPriv().caps()->avoidStencilBuffers()) {
         return &GrUserStencilSettings::kUnused;
     }
     static constexpr GrUserStencilSettings kReads(