Move GrContextPriv methods to their own .cpp file

Centralize these for my sanity. Most will also be parceled out to other contexts.

Change-Id: If0e7e98bcf66c4d8a3391f9b04e643ccc91af4ad
Reviewed-on: https://skia-review.googlesource.com/c/189488
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
diff --git a/src/gpu/GrResourceCache.h b/src/gpu/GrResourceCache.h
index 59141ad..c948864 100644
--- a/src/gpu/GrResourceCache.h
+++ b/src/gpu/GrResourceCache.h
@@ -233,11 +233,14 @@
 
     void getStats(Stats*) const;
 
+#if GR_TEST_UTILS
     void dumpStats(SkString*) const;
 
     void dumpStatsKeyValuePairs(SkTArray<SkString>* keys, SkTArray<double>* value) const;
 #endif
 
+#endif
+
 #ifdef SK_DEBUG
     int countUniqueKeysWithTag(const char* tag) const;
 #endif