Rename "user key" methods in vold

Rename methods that refer to "user key" to be more precise about what
they mean.  For more details, see the corresponding frameworks/base
changes (I202ebbfd2b4f79fedb3ed120a8ad81500c126894 and
I5894beb97823dced5954e405d779fada49c79e8d).

No change in behavior except for some changed log messages.

Flag: exempt, mechanical refactoring only
Test: presubmit
Change-Id: I9edcb557172395f4f6cf8e837efcc06fcfefb37d
diff --git a/VoldNativeService.h b/VoldNativeService.h
index 6debe77..e98aea8 100644
--- a/VoldNativeService.h
+++ b/VoldNativeService.h
@@ -112,14 +112,14 @@
 
     binder::Status setStorageBindingSeed(const std::vector<uint8_t>& seed);
 
-    binder::Status createUserKey(int32_t userId, int32_t userSerial, bool ephemeral);
-    binder::Status destroyUserKey(int32_t userId);
+    binder::Status createUserStorageKeys(int32_t userId, int32_t userSerial, bool ephemeral);
+    binder::Status destroyUserStorageKeys(int32_t userId);
 
-    binder::Status setUserKeyProtection(int32_t userId, const std::string& secret);
+    binder::Status setCeStorageProtection(int32_t userId, const std::string& secret);
 
     binder::Status getUnlockedUsers(std::vector<int>* _aidl_return);
-    binder::Status unlockUserKey(int32_t userId, int32_t userSerial, const std::string& secret);
-    binder::Status lockUserKey(int32_t userId);
+    binder::Status unlockCeStorage(int32_t userId, int32_t userSerial, const std::string& secret);
+    binder::Status lockCeStorage(int32_t userId);
 
     binder::Status prepareUserStorage(const std::optional<std::string>& uuid, int32_t userId,
                                       int32_t userSerial, int32_t flags);