Detach transform feedback when deleted.

Bug b/116778367

Change-Id: Iff07e00a36669d10518b83a6bfdb1e6af4ffcef3
Reviewed-on: https://swiftshader-review.googlesource.com/c/21688
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
diff --git a/src/OpenGL/libGLESv2/Context.cpp b/src/OpenGL/libGLESv2/Context.cpp
index 584b56d..866912c 100644
--- a/src/OpenGL/libGLESv2/Context.cpp
+++ b/src/OpenGL/libGLESv2/Context.cpp
@@ -1071,6 +1071,12 @@
 {
 	TransformFeedback *transformFeedbackObject = mTransformFeedbackNameSpace.remove(transformFeedback);
 
+	// Detach if currently bound.
+	if(mState.transformFeedback == transformFeedback)

+	{

+		mState.transformFeedback = 0;

+	}
+
 	if(transformFeedbackObject)
 	{
 		delete transformFeedbackObject;