D3D11 device context clears and flushes the state to release internal references before destruction.

TRAC #22231

Signed-off-by: Jamie Madill
Signed-off-by: Daniel Koch
Author: Geoff Lang

git-svn-id: https://angleproject.googlecode.com/svn/branches/dx11proto@1696 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/libGLESv2/renderer/Renderer11.cpp b/src/libGLESv2/renderer/Renderer11.cpp
index ecd85a7..a1a2c2f 100644
--- a/src/libGLESv2/renderer/Renderer11.cpp
+++ b/src/libGLESv2/renderer/Renderer11.cpp
@@ -77,6 +77,8 @@
 
     if (mDeviceContext)
     {
+        mDeviceContext->ClearState();
+        mDeviceContext->Flush();
         mDeviceContext->Release();
         mDeviceContext = NULL;
     }