[EasyUnlock] Move DataWithTimestamp out of ForegroundEidGenerator so it can be shared.

components/cryptauth/mock_foreground_eid_generator.cc

Index: components/cryptauth/mock_foreground_eid_generator.cc
diff --git a/components/cryptauth/mock_foreground_eid_generator.cc b/components/cryptauth/mock_foreground_eid_generator.cc
index 60fc35958c1ae8b48d9e0ca138bf3c91904829e8..2cd00c40aaa97b49f577df8d1f9f2201612ab5eb 100644
--- a/components/cryptauth/mock_foreground_eid_generator.cc
+++ b/components/cryptauth/mock_foreground_eid_generator.cc
@@ -24,9 +24,9 @@ MockForegroundEidGenerator::GenerateBackgroundScanFilter(
     return nullptr;
   }
 
-  std::unique_ptr<ForegroundEidGenerator::DataWithTimestamp> adjacent_data;
+  std::unique_ptr<EidDataWithTimestamp> adjacent_data;
   if (background_scan_filter_->adjacent_data) {
-    adjacent_data = base::MakeUnique<DataWithTimestamp>(
+    adjacent_data = base::MakeUnique<EidDataWithTimestamp>(
         background_scan_filter_->adjacent_data->data,
         background_scan_filter_->adjacent_data->start_timestamp_ms,
         background_scan_filter_->adjacent_data->end_timestamp_ms);
@@ -36,7 +36,7 @@ MockForegroundEidGenerator::GenerateBackgroundScanFilter(
                                    std::move(adjacent_data));
 }
 
-std::unique_ptr<ForegroundEidGenerator::DataWithTimestamp>
+std::unique_ptr<EidDataWithTimestamp>
 MockForegroundEidGenerator::GenerateAdvertisement(
     const std::string& advertising_device_public_key,
     const std::vector<BeaconSeed>& scanning_device_beacon_seeds) const {
@@ -44,9 +44,9 @@ MockForegroundEidGenerator::GenerateAdvertisement(
     return nullptr;
   }
 
-  return base::MakeUnique<DataWithTimestamp>(advertisement_->data,
-                                             advertisement_->start_timestamp_ms,
-                                             advertisement_->end_timestamp_ms);
+  return base::MakeUnique<EidDataWithTimestamp>(
+      advertisement_->data, advertisement_->start_timestamp_ms,
+      advertisement_->end_timestamp_ms);
 }
 
 std::vector<std::string>