[nativewindow] fix -Wreorder-init-list

C++20 will require members in a designated initializer to be in order
unlike C99.

Bug: 139945549
Test: mm
Change-Id: I9af163a79aa97f3b1a7e423614a82c920a09ab17
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>