Fix uniform block binding.

Bug swiftshader:2

Change-Id: I43c55f948a0816cf062b9b2e9d158c9a52fafdbc
Reviewed-on: https://swiftshader-review.googlesource.com/6930
Reviewed-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>
Tested-by: Nicolas Capens <capn@google.com>
diff --git a/src/OpenGL/libGLESv2/libGLESv3.cpp b/src/OpenGL/libGLESv2/libGLESv3.cpp
index f4bef0f..d1bb618 100644
--- a/src/OpenGL/libGLESv2/libGLESv3.cpp
+++ b/src/OpenGL/libGLESv2/libGLESv3.cpp
@@ -2960,7 +2960,7 @@
 			return error(GL_INVALID_VALUE);
 		}
 
-		programObject->bindUniformBlock(uniformBlockIndex, uniformBlockIndex);
+		programObject->bindUniformBlock(uniformBlockIndex, uniformBlockBinding);
 	}
 }