Remove OpenGL error checks that were causing errors.

The OpenGL error checks in those code itself raise OpenGL errors when
this code was called while building a display list (tracked using
bugle). Checks in this API is an overkill anyways. The called code
should to the checking if needed.

Change-Id: If1daaaa9a7c8c4131a11c2b6d52a10b9a18a162f

Rendering/OpenGL/vtkGLSLShaderDeviceAdapter2.cxx

@@ -20,7 +20,6 @@
 #include "vtkDataSetAttributes.h"
 #include "vtkObjectFactory.h"
 #include "vtkShaderProgram2.h"
-#include "vtkOpenGLError.h"
 
 #include <map>
 #include <string>
@@ -129,8 +128,6 @@ void vtkGLSLShaderDeviceAdapter2::SendAttribute(const char *attrname,
                                                const void *attribute,
                                                unsigned long offset)
 {
-  vtkOpenGLClearErrorMacro();
-
   int index;
   vtkInternal::MapOfStringToInt::iterator iter =
     this->Internal->AttributeIndicesCache.find(attrname);
@@ -280,7 +277,6 @@ void vtkGLSLShaderDeviceAdapter2::SendAttribute(const char *attrname,
     vtkErrorMacro("Unsupported attribute index: " << index);
     }
 
-  vtkOpenGLCheckErrorMacro("failed after SendAttribute");
   return;
 };