Do not migrate NetworkPrediction preference on Android.

chrome/browser/prefs/browser_prefs.cc

Index: chrome/browser/prefs/browser_prefs.cc
diff --git a/chrome/browser/prefs/browser_prefs.cc b/chrome/browser/prefs/browser_prefs.cc
index 35472d8239fd2ec25ccff8659267681492c4a850..ae35097e18ebc29d78e17c2e87d4ac6ac4df57ec 100644
--- a/chrome/browser/prefs/browser_prefs.cc
+++ b/chrome/browser/prefs/browser_prefs.cc
@@ -528,11 +528,14 @@ void MigrateUserPrefs(Profile* profile) {
   // Cleanup now-removed sync promo error message preference.
   // TODO(fdoray): Remove this when it's safe to do so (crbug.com/268442).
   prefs->ClearPref(kSyncPromoErrorMessage);
+  // Migrate kNetworkPredictionEnabled to kNetworkPredictionOptions when not on
+  // Android.  On Android, platform-specific code performs preference migration.
+  // TODO(bnc): https://crbug.com/401970  Remove migration code after some time.

[Bernhard Bauer, 2014/08/11 09:01:33]

Nit: Instead of "after some time", could you define an objective criterion here?
That way, even if you and me forget about this, someone else who comes across
this code can do the cleanup. 

[Bence, 2014/08/11 13:39:45]

Done.

+  chrome_browser_net::MigrateNetworkPredictionUserPrefs(prefs);
 #endif
 
   PromoResourceService::MigrateUserPrefs(prefs);
   translate::TranslatePrefs::MigrateUserPrefs(prefs, prefs::kAcceptLanguages);
-  chrome_browser_net::MigrateNetworkPredictionUserPrefs(prefs);
 
 #if defined(OS_MACOSX) && !defined(OS_IOS)
   autofill::AutofillManager::MigrateUserPrefs(prefs);