Adding Startup.WKWebViewBrowsingDataMigrationHasBeenPossible

Startup.WKWebViewBrowsingDataMigrationHasBeenPossible
is a boolean histogram that represents whether migration could
have been performed on this or a previous cold start.

BUG=535765

Review URL: https://codereview.chromium.org/1394633002

Cr-Commit-Position: refs/heads/master@{#352923}

2 files changed, 6 insertions, 0 deletions

diff --git a/ios/chrome/browser/pref_names.cc b/ios/chrome/browser/pref_names.cc
index c6b9a17f..ed59ad9 100644
--- a/ios/chrome/browser/pref_names.cc
+++ b/ios/chrome/browser/pref_names.cc
@@ -43,6 +43,11 @@ const char kIosBookmarkFolderDefault[] = "ios.bookmark.default_folder";
 // the bookmark promo dialog.
 const char kIosBookmarkPromoAlreadySeen[] = "ios.bookmark.promo_already_seen";
 
+// Boolean which indicates whether browsing data migration is/was possible in
+// this or a previous cold start.
+const char kBrowsingDataMigrationHasBeenPossible[] =
+    "ios.browsing_data_migration_controller.migration_has_been_possible";
+
 // Boolean which indicates if the user has already set a "do not backup" bit to
 // the OTR Profiles's state stash path to ensure that the folder is not
 // automatically synced to iCloud/iTunes.
diff --git a/ios/chrome/browser/pref_names.h b/ios/chrome/browser/pref_names.h
index 16e8f97..4903b1e 100644
--- a/ios/chrome/browser/pref_names.h
+++ b/ios/chrome/browser/pref_names.h
@@ -28,6 +28,7 @@ namespace prefs {
 extern const char kContextualSearchEnabled[];
 extern const char kIosBookmarkFolderDefault[];
 extern const char kIosBookmarkPromoAlreadySeen[];
+extern const char kBrowsingDataMigrationHasBeenPossible[];
 extern const char kOTRStashStatePathSystemBackupExcluded[];
 extern const char kIosHandoffToOtherDevices[];
 extern const char kLastSessionExitedCleanly[];