Split out methods in GrGpuResource::CacheAccess that can be called outside of the cache.

Review URL: https://codereview.chromium.org/923143002
diff --git a/bench/GrResourceCacheBench.cpp b/bench/GrResourceCacheBench.cpp
index 39007c3..61ab4d0 100644
--- a/bench/GrResourceCacheBench.cpp
+++ b/bench/GrResourceCacheBench.cpp
@@ -11,6 +11,7 @@
 #if SK_SUPPORT_GPU
 
 #include "GrGpuResource.h"
+#include "GrGpuResourcePriv.h"
 #include "GrContext.h"
 #include "GrGpu.h"
 #include "GrResourceCache.h"
@@ -45,7 +46,7 @@
         GrContentKey key;
         BenchResource::ComputeKey(i, &key);
         GrGpuResource* resource = SkNEW_ARGS(BenchResource, (gpu));
-        resource->cacheAccess().setContentKey(key);
+        resource->resourcePriv().setContentKey(key);
         resource->unref();
     }
 }