Description: Solve warnings

IssueNo: https://gitee.com/openharmony/graphic_ui/issues/I5GPJZ
Feature or Bugfix: Bugfix
Binary Source:No
Signed-off-by: liuyuxiang <liuyuxiang7@huawei.com>

frameworks/diagram/vertexgenerate/vertex_generate_stroke.cpp

@@ -73,6 +73,7 @@ uint32_t VertexGenerateStroke::GenerateVertex(float* x, float* y)
         switch (status_) {
             case INITIAL:
                 Rewind(0); // It will be ready immediately after initialization
+                /* fallthru */
             case READY:
                 VertexReady(verticesNum, cmd);
                 break;