[Build] Update Gradle to 8.12.1 and AGP to 8.8.1

[ParaskP7]

Issue: apps-infra-plans#174
Required By (for local builds): WPAndroid##21680

What?

This PR updates Gradle to 8.12.1 and AGP to 8.8.1 (context).

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Why?

This Gradle and AGP update is required by WPAndroid##21680 to avoid breaking local development abilities as it would severely deteriorate productivity (context).

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How?

Updating Gradle and AGP versions that match the WPAndroid##21680 PR related Gradle and AGP versions.

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Testing Instructions

1. Verify that all the CI checks are successful.
2. Smoke test the example app and verify everything is working as expected¹.
3. Follow the (3.) testing instructions on WPAndroid##21680 to test both apps, Jetpack and WordPress, using the composite builds.
4. Try to test for build time increases both, locally and on CI.
5. Locally, in addition to the debug variant, assemble/lint the release variant, and verify everything is working as expected.
   • Run: ./gradlew assembleRelease
   • Run: ./gradlew lintRelease

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Accessibility Testing Instructions N/A

Screenshots or screencast N/A

Footnotes

1. I tried following the README.md#Android instructions, starting the development server with the example app and all, but I am not sure I am doing it the right way. I get an app being launched with a black screen, which then points me to the browser (opening Chrome), where I can then add title/description and do things with this GBKit. Not sure if that's how the example app is supposed to be tested locally (please guide me). PS: On android/local.properties -> GUTENBERG_EDITOR_URL, I am using the network URL that the development server points to. 🤔 ↩

[ParaskP7]

FYI: I just updated trunk again but most importantly I included the new patch version of AGP (8.8.1) so that when this PR is merged we get all the fixes it includes.

[dcalhoun]

The test plan succeeded for me. Thank you for completing this upgrade. 🙇🏻‍♂️

I get an app being launched with a black screen, which then points me to the browser (opening Chrome), where I can then add title/description and do things with this GBKit.

No, launching the OS browser should not occur. The app's WebView should load GutenbergKit. I've encountered this issue as well. I have not identified the cause, but it occurs sporadically and I believe it may be related to Node.js server failures.

Specifically, it may relate to polyfills and bad caches. Temporarily removing the polyfills and restarting the Node.js server may fix the issue.

Polyfill removal diff

diff --git a/vite.config.js b/vite.config.js
index 7bc91b3..bfd8ff1 100644
--- a/vite.config.js
+++ b/vite.config.js
@@ -3,7 +3,6 @@
  */
 import { defineConfig } from 'vite';
 import react from '@vitejs/plugin-react';
-import { nodePolyfills } from 'vite-plugin-node-polyfills';
 
 export default defineConfig({
 	base: '',
@@ -11,7 +10,7 @@ export default defineConfig({
 		outDir: '../dist',
 		target: 'esnext',
 	},
-	plugins: [nodePolyfills(), react()],
+	plugins: [react()],
 	root: 'src',
 	css: {
 		preprocessorOptions: {

[ParaskP7]

The test plan succeeded for me. Thank you for completing this upgrade. 🙇🏻‍♂️

Awesome @dcalhoun , thank you so much for reviewing and testing this change! 🙇 ❤️ 🚀

No, launching the OS browser should not occur. The app's WebView should load GutenbergKit. I've encountered this issue as well. I have not identified the cause, but it occurs sporadically and I believe it may be related to Node.js server failures.

This is great to know, I am glad this (at least) worked on your side as expected! 👍

Specifically, it may relate to polyfills and bad caches. Temporarily removing the polyfills and restarting the Node.js server may fix the issue.

Awesome, thanks for sharing this diff, I'll definitely use it next time I'll need it. 💯

[ParaskP7]

FYI: Now that I got the 👍s on this I am going to merge this and continue with the rest of the merge instruction steps within JP/WPAndroid#21680.