Cleaning up the serialization change.
Renaming the define to be more in line with what it does and removing the host stub header file.

Change-Id: Ibd3a0a6a398c7f81cc661f71e4478707fe1679ed

rsSampler.cpp

diff --git a/rsSampler.cpp b/rsSampler.cpp
index c80aecc..db2383a 100644
--- a/rsSampler.cpp
+++ b/rsSampler.cpp
@@ -14,15 +14,11 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_RS_BUILD_FOR_HOST
+#include "rsContext.h"
+#ifndef ANDROID_RS_SERIALIZE
 #include <GLES/gl.h>
 #include <GLES/glext.h>
-#include "rsContext.h"
-#else
-#include "rsContextHostStub.h"
-#include <OpenGL/gl.h>
-#include <OpenGL/glext.h>
-#endif //ANDROID_RS_BUILD_FOR_HOST
+#endif //ANDROID_RS_SERIALIZE
 
 #include "rsSampler.h"