Do not use dynamic_cast if RTTI is disabled.
Review URL: https://codereview.appspot.com/7250043

git-svn-id: https://angleproject.googlecode.com/svn/branches/dx11proto@1808 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/libGLESv2/renderer/Image11.cpp b/src/libGLESv2/renderer/Image11.cpp
index a8a703b..677b875 100644
--- a/src/libGLESv2/renderer/Image11.cpp
+++ b/src/libGLESv2/renderer/Image11.cpp
@@ -37,7 +37,7 @@
 
 Image11 *Image11::makeImage11(Image *img)
 {
-    ASSERT(dynamic_cast<rx::Image11*>(img) != NULL);
+    ASSERT(HAS_DYNAMIC_TYPE(rx::Image11*, img));
     return static_cast<rx::Image11*>(img);
 }