Revert bits of aosp/2632890

aosp/2632890 actually started return strings instead of actual argument values — revert it.

The underlying problem with using debug tracks with duplicated columns is going to be addressed by aosp/2630775.

Change-Id: I60e5bb80b30209b477d51a96708742e086f3ca75
diff --git a/ui/src/tracks/debug/slice_track.ts b/ui/src/tracks/debug/slice_track.ts
index 2d5bd2d..0c70517 100644
--- a/ui/src/tracks/debug/slice_track.ts
+++ b/ui/src/tracks/debug/slice_track.ts
@@ -119,7 +119,7 @@
           cast(${dur} as int) as dur,
           printf('%s', ${sliceColumns.name}) as name
           ${argColumns.length > 0 ? ',' : ''}
-          ${argColumns.map((c) => `'${c}' as '${ARG_PREFIX}${c}'`).join(',')}
+          ${argColumns.map((c) => `${c} as ${ARG_PREFIX}${c}`).join(',')}
         from ${sqlViewName}
       )
       select