Creator版本：2.4.5
Mac
选择两个以上的资源时改变面板大小会报错:
TypeError: Cannot read property 'resize' of null
at Vue.resize (/Applications/CocosCreator/Creator/2.4.5/CocosCreator.app/Contents/Resources/app.asar/editor/builtin/inspector/inspectors/texture.ccc:1:2968)
at Vue.resize (app://node_modules/vue/dist/vue.js:220:72)
at HTMLElement.panel-resize (/Applications/CocosCreator/Creator/2.4.5/CocosCreator.app/Contents/Resources/app.asar/editor/builtin/inspector/panel/index.ccc:1:1792)
at Object.fire (/Applications/CocosCreator/Creator/2.4.5/CocosCreator.app/Contents/Resources/app.asar/editor-framework/lib/renderer/ui/utils/dom-utils.ccc:1:1642)
at HTMLElement._notifyResize (/Applications/CocosCreator/Creator/2.4.5/CocosCreator.app/Contents/Resources/app.asar/editor-framework/lib/renderer/ui/panel/panel.ccc:1:2764)
at HTMLElement._notifyResize (/Applications/CocosCreator/Creator/2.4.5/CocosCreator.app/Contents/Resources/app.asar/editor-framework/lib/renderer/ui/behaviors/dockable.ccc:1:695)
at HTMLDocument.v (/Applications/CocosCreator/Creator/2.4.5/CocosCreator.app/Contents/Resources/app.asar/editor-framework/lib/renderer/ui/dock/resizer.ccc:1:3566)
