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/gl/GrGLRenderTarget.cpp b/src/gpu/gl/GrGLRenderTarget.cpp
index 382457d..e996588 100644
--- a/src/gpu/gl/GrGLRenderTarget.cpp
+++ b/src/gpu/gl/GrGLRenderTarget.cpp
@@ -6,8 +6,8 @@
  */
 
 #include "GrGLRenderTarget.h"
-
 #include "GrContext.h"
+#include "GrContextPriv.h"
 #include "GrGLGpu.h"
 #include "GrGLUtil.h"
 #include "GrGpuResourcePriv.h"
@@ -187,7 +187,7 @@
 }
 
 bool GrGLRenderTarget::canAttemptStencilAttachment() const {
-    if (this->getGpu()->getContext()->caps()->avoidStencilBuffers()) {
+    if (this->getGpu()->getContext()->contextPriv().caps()->avoidStencilBuffers()) {
         return false;
     }