Add Histogram Macros to Skia

include/config/SkUserConfig.h

 
 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef SkUserConfig_DEFINED
@@ skipping 135 matching lines @@
 
 /* The PDF generation code uses Path Ops to handle complex clipping paths,
  * but at this time, Path Ops is not release ready yet. So, the code is
  * hidden behind this #define guard. If you are feeling adventurous and
  * want the latest and greatest PDF generation code, uncomment the #define.
  * When Path Ops is release ready, the define guards and this user config
  * define should be removed entirely.
  */
 //#define SK_PDF_USE_PATHOPS_CLIPPING
 
+/* Skia makes use of histogram logging macros to trace the frequency of
+ * events. By default, Skia provides no-op versions of these macros.
+ * Skia consumers can provide their own definitions of these macros to
+ * integrate with their histogram collection backend.
+ */
+//#define SK_HISTOGRAM_BOOLEAN(name, value)
+//#define SK_HISTOGRAM_ENUMERATION(name, value, boundary_value)
+
 #endif