Add test for wgpu_request_animation_frame_loop().

Author: juj

test/wgpu_request_animation_frame_loop.cpp

@@ -0,0 +1,26 @@
+// flags: -sEXIT_RUNTIME=0
+
+#include "lib_webgpu.h"
+#include <assert.h>
+
+int num_calls = 0;
+
+double previous_time;
+WGPU_BOOL raf(double time, void *userData)
+{
+  assert(time > previous_time);
+  previous_time = time;
+
+  assert(userData == (void*)42);
+  if (++num_calls > 100)
+  {
+    EM_ASM(window.close());
+    return WGPU_FALSE;
+  }
+  return WGPU_TRUE;
+}
+
+int main()
+{
+  wgpu_request_animation_frame_loop(raf, (void*)42);
+}