[Sync] Split encryption state and logic out of PSS and SBHI.

components/sync/engine/fake_sync_engine.h

Index: components/sync/engine/fake_sync_engine.h
diff --git a/components/sync/engine/fake_sync_engine.h b/components/sync/engine/fake_sync_engine.h
index b71bec98c96201aed7812c68f87efab60a26fea6..f2dcf2c23cd6e1ad7dab96fec6e27c2eb2329150 100644
--- a/components/sync/engine/fake_sync_engine.h
+++ b/components/sync/engine/fake_sync_engine.h
@@ -39,7 +39,7 @@ class FakeSyncEngine : public SyncEngine {
   void SetEncryptionPassphrase(const std::string& passphrase,
                                bool is_explicit) override;
 
-  bool SetDecryptionPassphrase(const std::string& passphrase) override;
+  void SetDecryptionPassphrase(const std::string& passphrase) override;
 
   void StopSyncingForShutdown() override;
 
@@ -68,12 +68,6 @@ class FakeSyncEngine : public SyncEngine {
 
   bool HasUnsyncedItems() const override;
 
-  bool IsNigoriEnabled() const override;
-
-  PassphraseType GetPassphraseType() const override;
-
-  base::Time GetExplicitPassphraseTime() const override;
-
   bool IsCryptographerReady(const BaseTransaction* trans) const override;
 
   void GetModelSafeRoutingInfo(ModelSafeRoutingInfo* out) const override;