Add some missing `#include <assert.h>` for Windows build when compiling without RTC tests (rtc_include_tests = false) with the MSVC compiler (is_clang=false, use_lld=false). Bug: None Change-Id: Ie9861100efeae87f4c4e29303d62293ad541125a Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/158533 Reviewed-by: Patrik Höglund <phoglund@webrtc.org> Reviewed-by: Gustaf Ullberg <gustaf@webrtc.org> Commit-Queue: Patrik Höglund <phoglund@webrtc.org> Cr-Commit-Position: refs/heads/master@{#29811}