DXGI 1.2 is required to create a swap chain for a HWND owned by another
process.  This fix will allow us to fall back to creating a Renderer9 if
DXGI 1.2 is not available instead of failing to create the swap chain
later.

BUG=angle:562

Change-Id: I01b08ffb262bc3f9c86d244168df14eba52c5bdc
Reviewed-on: https://chromium-review.googlesource.com/186980Reviewed-by: Shannon Woods <shannonwoods@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>