Do not copy labels for generated local repo

The copied label such as "gvhp_exportpath" may interfere the uninstallation
feature and package migration feature since those feature will try to remove
the generated file instead of the ones they are copied from.

Change-Id: I28f1d5225740fe2e5ff61ae3ceef14f787a5f8cf

Author: chkuang-g

source/AndroidResolver/src/PlayServicesResolver.cs

@@ -2278,9 +2278,12 @@ internal static string CopyAssetAndLabel(string sourceLocation, string targetLoc
                     sourceLocation, targetLocation),
                     level: LogLevel.Verbose);
 
-            if (!AssetDatabase.CopyAsset(sourceLocation, targetLocation)) {
-                return String.Format("Failed to copy {0} to {1}.",
-                        sourceLocation, targetLocation);
+            // Use File.Copy() instead of AssetDatabase.CopyAsset() to prevent copying meta data.
+            try {
+                File.Copy(sourceLocation, targetLocation);
+            } catch (Exception e) {
+                return String.Format("Failed to copy {0} to {1} due to {2}",
+                        sourceLocation, targetLocation, e.ToString());
             }
 
             var unlabeledAssets = new HashSet<string>();