am f45c5100: partially implement external display clipping

                drawWormhole(hw, region);

            }

        }

        if (hw->getDisplayType() >= DisplayDevice::DISPLAY_EXTERNAL) {

            // TODO: just to be on the safe side, we don't set the

            // scissor on the main display. It should never be needed

            // anyways (though in theory it could since the API allows it).

            const Rect& bounds(hw->getBounds());

            const Transform& tr(hw->getTransform());

            const Rect scissor(tr.transform(hw->getViewport()));

            if (scissor != bounds) {

                // scissor doesn't match the screen's dimensions, so we

                // need to clear everything outside of it and enable

                // the GL scissor so we don't draw anything where we shouldn't

                const GLint height = hw->getHeight();

                glScissor(scissor.left, height - scissor.bottom,

                        scissor.getWidth(), scissor.getHeight());

                // clear everything unscissored

                glClearColor(0, 0, 0, 0);

                glClear(GL_COLOR_BUFFER_BIT);

                // enable scissor for this frame

                glEnable(GL_SCISSOR_TEST);

            }

        }

    }

    /*

            }

        }

    }

    // disable scissor at the end of the frame

    glDisable(GL_SCISSOR_TEST);

}

void SurfaceFlinger::drawWormhole(const sp<const DisplayDevice>& hw,