Pref service: add support for tracked prefs.

components/user_prefs/tracked/pref_hash_filter.h

Index: components/user_prefs/tracked/pref_hash_filter.h
diff --git a/components/user_prefs/tracked/pref_hash_filter.h b/components/user_prefs/tracked/pref_hash_filter.h
index 87c3f036ab12e359351fcef78cfd425fcbaf7e83..5e19e96777a0b63a6af80159372180dabfdabfd9 100644
--- a/components/user_prefs/tracked/pref_hash_filter.h
+++ b/components/user_prefs/tracked/pref_hash_filter.h
@@ -21,6 +21,7 @@
 #include "components/user_prefs/tracked/hash_store_contents.h"
 #include "components/user_prefs/tracked/interceptable_pref_filter.h"
 #include "components/user_prefs/tracked/tracked_preference.h"
+#include "services/preferences/public/interfaces/preferences_configuration.mojom-shared.h"
 
 class PrefHashStore;
 class PrefService;
@@ -45,22 +46,11 @@ class PrefRegistrySyncable;
 // are changed.
 class PrefHashFilter : public InterceptablePrefFilter {
  public:
-  enum EnforcementLevel { NO_ENFORCEMENT, ENFORCE_ON_LOAD };

[gab, 2017/03/13 16:52:02]

Can we turn these into "enum class" in a precursor CL and forward all of the
deltas caused by this to that CL (this one is already big enough like this and
it's hard to review with all the no-op diffs caused by this).

[Sam McNally, 2017/03/14 02:01:35]

https://codereview.chromium.org/2752533002/

-
-  enum PrefTrackingStrategy {
-    // Atomic preferences are tracked as a whole.
-    TRACKING_STRATEGY_ATOMIC,
-    // Split preferences are dictionaries for which each top-level entry is
-    // tracked independently. Note: preferences using this strategy must be kept
-    // in sync with TrackedSplitPreferences in histograms.xml.
-    TRACKING_STRATEGY_SPLIT,
-  };
-
-  enum ValueType {
-    VALUE_IMPERSONAL,
-    // The preference value may contain personal information.
-    VALUE_PERSONAL,
-  };
+  using EnforcementLevel =
+      prefs::mojom::TrackedPreferenceMetadata_EnforcementLevel;
+  using PrefTrackingStrategy =
+      prefs::mojom::TrackedPreferenceMetadata_PrefTrackingStrategy;
+  using ValueType = prefs::mojom::TrackedPreferenceMetadata_ValueType;
 
   struct TrackedPreferenceMetadata {
     size_t reporting_id;