Route diagnostic hooks through platform services

src/app_events.cpp

@@ -79,24 +79,12 @@ bool App::clipboard_set_text(const std::string& s)
 
 void App::stacktrace()
 {
-#if __OSX__
-    NSString* callstack = [[NSThread callStackSymbols] componentsJoinedByString:@"\n"];
-    LOG("callstack:\n%s", [callstack cStringUsingEncoding:NSUTF8StringEncoding]);
-#endif
+    active_platform_services().log_stacktrace();
 }
 
 void App::crash_test()
 {
-#ifdef __IOS__
-    [ios_view crash];
-#elif __OSX__
-    [osx_view hockeyapp_crash];
-#elif defined(_WIN32)
-    __debugbreak();
-#elif defined(__ANDROID__)
-    int *x = nullptr; *x = 42;
-    LOG("%d", *x);
-#endif
+    active_platform_services().trigger_crash_test();
 }
 
 void App::tick(float dt)