refactor(framework): Deprecate RenderScheduler in favor of Render.js

[vladitasev]

Changes:

• New module: Render.js that implements all functionality that used to be in RenderScheduler.js. This allows the code to be tree-shaken, unlike as it was before (with a static class).
• whenFinished renamed to renderFinished.
• RenderScheduler.js is deprecated, although not deleted yet, and it proxies the 3 important functions that external users normally call: renderImmediately, renderDeferred and whenFinished.
• The register and deregister functions have been merged with renderImmediately and cancelRender respectively and no longer exist.
• The reRenderAllUI5Elements function is now async and awaits for renderFinished internally. This was changed because normally when this function was called, renderFinished was called on the next line.
• All test assets have been reworked to access renderFinished from the window["sap-ui-webcomponents-bundle"] global variable rather than from the RenderScheduler global variable.

Additionally, upgraded Chromedriver to version 88.

BREAKING CHANGES:

• RenderScheduler.js deprecated. The file will be deleted in a future release. If you were using some of its methods, import these methods from the new Render.js module. For example, if you were using:

import RenderScheduler from "@ui5/webcomponents-base/dist/RenderScheduler.js";
RenderScheduler.renderImmediately(myComponent);
RenderScheduler.renderDeferred(myComponent);
await RenderScheduler.whenFinished();

change to:

import { renderFinished, renderImmediately, renderDeferred } from "@ui5/webcomponents-base/dist/Render.js";
renderImmediately(myComponent);
renderDeferred(myComponent);
await renderFinished();

• whenFinished from RenderScheduler.js renamed to renderFinished and now exported by Render.js. For usage, see the previous example

[pskelin]

not related to this change, but I think we should improve this with a loop, as the DOM Update promise might result in more undefined custom elements.

[pskelin]

can you add a warning in the console, otherwise it is too easy to miss.

[pskelin]

Without the RenderSchduler, whenFinished sounds too generic.

I also think the when... sounds good when followed by a then...

Maybe we can drop the when a use the render verb, something like
await renderFinished()