Add null egl/gles stub support

Change-Id: I41372585202f69ef31a4ef95efc75fb7a1ff7289
diff --git a/libs/hwui/tests/main.cpp b/libs/hwui/tests/main.cpp
index 0431e22..bffbbef 100644
--- a/libs/hwui/tests/main.cpp
+++ b/libs/hwui/tests/main.cpp
@@ -95,16 +95,16 @@
         animation.createContent(width, height, renderer);
         endRecording(renderer, rootNode);
 
-        for (int i = 0; i < 150; i++) {
+        for (int i = 0; i < animation.getFrameCount(); i++) {
+#if !HWUI_NULL_GPU
             testContext.waitForVsync();
+#endif
 
             ATRACE_NAME("UI-Draw Frame");
             animation.doFrame(i);
             proxy->syncAndDrawFrame();
         }
 
-        sleep(5);
-
         rootNode->decStrong(nullptr);
     }
 };