Add new debug option to force 4x MSAA in OpenGL ES 2.0 apps

    egl_connection_t* const cnx = &gEGLImpl;

    if (cnx->dso) {

        if (attrib_list) {

            char value[PROPERTY_VALUE_MAX];

            property_get("debug.egl.force_msaa", value, "false");

            if (!strcmp(value, "true")) {

                size_t attribCount = 0;

                EGLint attrib = attrib_list[0];

                // Only enable MSAA if the context is OpenGL ES 2.0 and

                // if a depth buffer is requested

                const EGLint *attribRendererable = NULL;

                const EGLint *attribCaveat = NULL;

                // Count the number of attributes and look for

                // EGL_RENDERABLE_TYPE and ELG_DEPTH_SIZE

                while (attrib != EGL_NONE) {

                    attrib = attrib_list[attribCount];

                    switch (attrib) {

                        case EGL_RENDERABLE_TYPE:

                            attribRendererable = &attrib_list[attribCount];

                            break;

                        case EGL_CONFIG_CAVEAT:

                            attribCaveat = &attrib_list[attribCount];

                            break;

                    }

                    attribCount++;

                }

                if (attribRendererable && attribRendererable[1] == EGL_OPENGL_ES2_BIT &&

                        (!attribCaveat || attribCaveat[1] != EGL_NONE)) {

                    // Insert 2 extra attributes to force-enable MSAA 4x

                    EGLint aaAttribs[attribCount + 4];

                    aaAttribs[0] = EGL_SAMPLE_BUFFERS;

                    aaAttribs[1] = 1;

                    aaAttribs[2] = EGL_SAMPLES;

                    aaAttribs[3] = 4;

                    memcpy(&aaAttribs[4], attrib_list, attribCount * sizeof(EGLint));

                    EGLint numConfigAA;

                    EGLBoolean resAA = cnx->egl.eglChooseConfig(

                            dp->disp.dpy, aaAttribs, configs, config_size, &numConfigAA);

                    if (resAA == EGL_TRUE && numConfigAA > 0) {

                        ALOGD("Enabling MSAA 4x");

                        *num_config = numConfigAA;

                        return resAA;

                    }

                }

            }

        }

        res = cnx->egl.eglChooseConfig(

                dp->disp.dpy, attrib_list, configs, config_size, num_config);

    }