Disable Skia histograms until issues can be debugged.

Skia histograms are generating invalid data. Disable them until we have
time to debug further.

Review-Url: https://codereview.chromium.org/2185263002
Cr-Commit-Position: refs/heads/master@{#408759}

skia/config/SkUserConfig.h

@@ -17,8 +17,6 @@
 #ifndef SkUserConfig_DEFINED
 #define SkUserConfig_DEFINED
 
-#include "skia/ext/skia_histogram.h"
-
 /*  SkTypes.h, the root of the public header files, does the following trick:
 
     #include <SkPreConfig.h>