优化执行 node->_setColorDirty(false)的时机

[finscn]

只有在 colorDirty 真正发挥过作用后 ,再执行 node->_setColorDirty(false).

目前的逻辑存在一个 bug:

某帧:

• node.colorDirty=true,
• 但是 entity.isEnabled === false,
• 那么 entity 的 透明度并不会被更新.
• 可是在这一帧 node.colorDirty 仍然被设置为了 false.

下一帧:

• entity.isEnabled === true 了,
• 但是 node.colorDirty 在上一帧已经被设置为 false
• 当前帧 entity 的 透明度仍然不会被更新

其实 cocos在 ts 端的逻辑也是 只有 visible 时, 才去修改 opacityDirty .

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我在实际项目中遇到的现象是
对 某个当前不可用 的 label 节点设置 透明度 , 当节点可用时 之前设置的透明度无效.

Re: #

Changelog

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• needs automatic test cases check.

  Manual trigger with @cocos-robot run test cases afterward.

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Compatibility Check

This pull request:

• changes public API, and have ensured backward compatibility with deprecated features.
• affects platform compatibility, e.g. system version, browser version, platform sdk version, platform toolchain, language version, hardware compatibility etc.
• affects file structure of the build package or build configuration which requires user project upgrade.
• introduces breaking changes, please list all changes, affected features and the scope of violation.