Fix errors on error paths found by oomer.

* Use-after-free because we free network before dht in one case.
* Various unchecked allocs in tests (not so important).
* We used to not check whether ping arrays were actually allocated in DHT.
* `ping_kill` and `ping_array_kill` used to crash when passing NULL.

Also:
* Added an assert in all public API functions to ensure tox isn't NULL.
  The error message you get from that is a bit nicer than "Segmentation
  fault" when clients (or our tests) do things wrong.
* Decreased the sleep time in iterate_all_wait from 20ms to 5ms.
  Everything seems to still work with 5ms, and this greatly decreases
  the amount of time spent per test run, making oomer run much faster.

2 files changed, 4 insertions, 4 deletions

diff --git a/toxav/ring_buffer_test.cc b/toxav/ring_buffer_test.cc
index 672ee2ce..667f90e3 100644
--- a/toxav/ring_buffer_test.cc
+++ b/toxav/ring_buffer_test.cc
@@ -1,11 +1,11 @@
 #include "ring_buffer.h"
 
+#include <gtest/gtest.h>
+
 #include <algorithm>
 #include <cassert>
 #include <vector>
 
-#include <gtest/gtest.h>
-
 namespace {
 
 template <typename T>
diff --git a/toxav/rtp_test.cc b/toxav/rtp_test.cc
index b0854142..bd94cc9c 100644
--- a/toxav/rtp_test.cc
+++ b/toxav/rtp_test.cc
@@ -1,9 +1,9 @@
 #include "rtp.h"
 
-#include "../toxcore/crypto_core.h"
-
 #include <gtest/gtest.h>
 
+#include "../toxcore/crypto_core.h"
+
 namespace {
 
 RTPHeader random_header() {