FBE: set TW_IS_FBE based on whether key version path exists

- Should not be determined by whether support exists in TWRP
- Set to 0 by default if FBE is not detected

This also prevents the wrappedkey check from running
on FDE devices

Change-Id: I85d1952facdfafdaa1571fc1b11d4b4b7d9ba48e

partition.cpp

@@ -723,10 +723,10 @@ void TWPartition::Setup_Data_Partition(bool Display_Error) {
 
 bool TWPartition::Decrypt_FBE_DE() {
 if (TWFunc::Path_Exists("/data/unencrypted/key/version")) {
+		DataManager::SetValue(TW_IS_FBE, 1);
 		LOGINFO("File Based Encryption is present\n");
 #ifdef TW_INCLUDE_FBE
 	Is_FBE = true;
-	DataManager::SetValue(TW_IS_FBE, 1);
 	ExcludeAll(Mount_Point + "/convert_fbe");
 	ExcludeAll(Mount_Point + "/unencrypted");
 	ExcludeAll(Mount_Point + "/misc/vold/user_keys");
@@ -777,6 +777,7 @@ if (TWFunc::Path_Exists("/data/unencrypted/key/version")) {
 		LOGERR("FBE found but FBE support not present in TWRP\n");
 #endif
 	}
+	DataManager::SetValue(TW_IS_FBE, 0);
 	return false;
 }