[v3.8.6] Optimize size for particle-system.ts

[dumganhar]

Re: #

Changelog

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Continuous Integration

This pull request:

• needs automatic test cases check.

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

• does not change any runtime related code or build configuration

  If any reviewer thinks the CI checks are needed, please uncheck this option, then close and reopen the issue.

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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.

[github-actions]

👍 Package size ⤵ -1172 bytes, old: 5270176, new: 5269004

Interface Check Report

! WARNING this pull request has changed these public interfaces:

@@ -46637,9 +46637,9 @@
         protected onEnable(): void;
         protected onDisable(): void;
         protected update(dt: number): void;
         protected beforeRender(): void;
-        protected _onVisibilityChange(val: any): void;
+        protected _onVisibilityChange(val: number): void;
         /**
          * @ignore
          */
         get isPlaying(): boolean;

[minggo]

Why change them to delare?

[dumganhar]

It is assigned in constructor. If don't use declare, there will be two assignments in the generated js file.

constructor () {
    ...
    this. _isStopped = void 0;
    this. _isStopped = false;
    ...
}