Examples: Fix d749d49903fb0eb56b08961d989ed90a9d97c28b missing the deletion code. (#1217)

examples/opengl3_example/imgui_impl_glfw_gl3.cpp

@@ -157,6 +157,7 @@ void ImGui_ImplGlfwGL3_RenderDrawData(ImDrawData* draw_data)
             idx_buffer_offset += pcmd->ElemCount;
         }
     }
+    glDeleteVertexArrays(1, &vao_handle);
 
     // Restore modified GL state
     glUseProgram(last_program);

examples/sdl_opengl3_example/imgui_impl_sdl_gl3.cpp

@@ -151,6 +151,7 @@ void ImGui_ImplSdlGL3_RenderDrawData(ImDrawData* draw_data)
             idx_buffer_offset += pcmd->ElemCount;
         }
     }
+    glDeleteVertexArrays(1, &vao_handle);
 
     // Restore modified GL state
     glUseProgram(last_program);