Adds makeSwapChain9/11 functions.

TRAC #22134

Signed-off-by: Nicolas Capens
Signed-off-by: Daniel Koch

git-svn-id: https://angleproject.googlecode.com/svn/branches/dx11proto@1477 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/libGLESv2/renderer/SwapChain11.cpp b/src/libGLESv2/renderer/SwapChain11.cpp
index bb2a92e..b1c5ec3 100644
--- a/src/libGLESv2/renderer/SwapChain11.cpp
+++ b/src/libGLESv2/renderer/SwapChain11.cpp
@@ -316,4 +316,11 @@
     return mOffscreenTexture;
 }
 
+SwapChain11 *SwapChain11::makeSwapChain11(SwapChain *swapChain)
+{
+    ASSERT(dynamic_cast<rx::SwapChain11*>(swapChain) != NULL);
+    return static_cast<rx::SwapChain11*>(swapChain);
 }
+
+}
+