Remove unused DRP code for migrating prefs

components/data_reduction_proxy/core/browser/data_reduction_proxy_prefs.h

Index: components/data_reduction_proxy/core/browser/data_reduction_proxy_prefs.h
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_prefs.h b/components/data_reduction_proxy/core/browser/data_reduction_proxy_prefs.h
index abf56ea3191661f6d154a1ba97f494432f23ec6d..891e302cb97b6f61199b5f5bc8535cd1387440f7 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_prefs.h
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_prefs.h
@@ -29,11 +29,6 @@ void RegisterSimpleProfilePrefs(PrefRegistrySimple* registry);
 // reduction proxy.
 void RegisterPrefs(PrefRegistrySimple* registry);
 
-// Migrates the prefs that are used to record compression statistics from |src|
-// to |dest|.
-// TODO(bengr): Remove this in M-43.
-void MigrateStatisticsPrefs(PrefService* src, PrefService* dest);

[bengr, 2016/10/27 18:28:37]

Compression history data will be lost for users who upgrade from <M40. This CL
makes sense now, as this is a tiny fraction of the population.

[tbansal1, 2016/10/27 20:12:45]

This is currently an unreachable function. I am not sure when the call was
removed.

[tbansal1, 2016/10/27 20:22:23]

Dug more.

It used to be called in chrome/browser/profiles/profile_impl.cc:
https://codereview.chromium.org/652743004/diff/170001/chrome/browser/profiles...

But, it seems it was accidentally removed 3 month later:
https://codereview.chromium.org/778463002/

-
 }  // namespace data_reduction_proxy
 
 #endif  // COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_DATA_REDUCTION_PROXY_PREFS_H_