Use DUPLICATE_SAME_ACCESS to duplicate privileges

When launching a process with admin rights we can't duplicate the
process handle with dwDesiredAccess == PROCESS_QUERY_INFORMATION.
But we don't need to - we just need the same rights we have to the
original handle. So we should instead set dwOptions to
DUPLICATE_SAME_ACCESS.

This is an update to correct the flaw added in crrev.com/c/1155498

Bug: 871522
Change-Id: Ib5e526c1a1dfef07e6bb5e6d4d64e12c2d4c3eed
Reviewed-on: https://chromium-review.googlesource.com/1173499Reviewed-by: Nick Carter <nick@chromium.org>
Reviewed-by: Robert Liao <robliao@chromium.org>
Commit-Queue: Bruce Dawson <brucedawson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#583000}

content/public/browser/child_process_data.cc

@@ -18,7 +18,7 @@ void ChildProcessData::SetHandle(base::ProcessHandle process) {
   } else {
     BOOL result =
         ::DuplicateHandle(::GetCurrentProcess(), process, ::GetCurrentProcess(),
-                          &handle_to_set, PROCESS_QUERY_INFORMATION, FALSE, 0);
+                          &handle_to_set, 0, FALSE, DUPLICATE_SAME_ACCESS);
     auto err = GetLastError();
     CHECK(result) << process << " " << err;
   }