anchor.diff:      final compileSuccess =
           gl.getShaderParameter(shader, RenderingContext2.COMPILE_STATUS);
       if (!compileSuccess) {
  -      print(
  -          '$runtimeType - Error compiling shader: ${gl.getShaderInfoLog(shader)}');
         success = false;
  +      throw new ArgumentError(
  +          '$runtimeType - Error compiling shader $vShaderFile or $fShaderFile: ${gl.getShaderInfoLog(shader)}');
       }
       return shader;
     }
  
positive.code:     }
      for (Attrib attribute in attributes) {
        final attribLocation = gl.getAttribLocation(program, attribute.name);
        gl
          ..vertexAttribPointer(
              attribLocation,
  
negative.code:       buffers[attribute] = buffer;
      }
      final attribLocation = gl.getAttribLocation(program, attribute);
      if (attribLocation == -1) {
        throw new ArgumentError(
            'Attribute $attribute not found in shader $vShaderFile}');
      }
      gl
        ..bindBuffer(RenderingContext.ARRAY_BUFFER, buffer)
        ..bufferData(RenderingContext.ARRAY_BUFFER, items, usage)
  