Merge pull request matrix-org#1848 from matrix-org/valere/expose_own_device_creation_ts

Add own device creation ts in crypto API

Author: BillCarsonFr

MatrixSDK/Crypto/MXCrypto.h

@@ -95,6 +95,12 @@ extern NSString *const MXDeviceListDidUpdateUsersDevicesNotification;
  */
 @property (nullable, nonatomic, readonly) NSString *deviceEd25519Key;
 
+
+/**
+* The user device creation in local timestamp, milliseconds since epoch.
+*/
+@property (nonatomic, readonly) UInt64 deviceCreationTs;
+
 /**
  The key backup manager.
  */

MatrixSDK/Crypto/MXCrypto.m

@@ -1422,6 +1422,12 @@ - (NSString *)olmVersion
 #endif
 }
 
+- (uint64_t)deviceCreationTs
+{
+    // Device creation timestamp is not support in legacy crypto
+    return 0;
+}
+
 
 #pragma mark - Gossipping
 

MatrixSDK/Crypto/MXCryptoV2.swift

@@ -56,6 +56,11 @@ class MXCryptoV2: NSObject, MXCrypto {
         return machine.deviceEd25519Key
     }
 
+    var deviceCreationTs: UInt64 {
+        // own device always exists
+        return machine.device(userId: machine.userId, deviceId: machine.deviceId)!.firstTimeSeenTs
+    }
+    
     let backup: MXKeyBackup?
     let keyVerificationManager: MXKeyVerificationManager
     let crossSigning: MXCrossSigning