Hiding the Pesto demo from Gallery

[sethladd]

Getting ready to update the Gallery in the public store, we noticed there are a few fidelity and performance issues with Pesto. We don't believe we can address the issues in time for the release, so we'd like to hide the Pesto demo in the meantime.

Fidelity (and some performance) issues affecting Pesto (and thus, people's perception of Flutter)

• Pesto: Image persists on a higher layer than the toolbar when contracting down #7709
• Performance issues with Gallery on Sony Xperia XZ #7541
• Abrupt image resize during hero transition #7221
• Flutter Gallery recipe browser transition jank #6920
• Pesto recipe page layout only partially fills the screen on a tablet #6742
• Pesto logo has inconsistent sharpness. #5906
• Gallery, Pesto: non-fading app bar when opening a recipe #5350
• Gallery, Pesto: FAB has square shadow while transitioning up #5203
• Gallery, Pesto: missing frames when hero'ing up a recipe in Pesto #5045
• Gallery, Pesto: missing frames when shrinking a recipe #5042
• Pesto: motion for the recipe going full screen #4436

[HansMuller]

This is easily done, if pesto is also removed from the gallery's unit test and performance benchmark.

Maybe we should just temporarily remove Pesto, until the app store build has shipped, and then restore it?

[eseidelGoogle]

@HansMuller can you do this?

[HansMuller]

Yes, that's what I meant by "This is easily done" :-).

I'd posed a question too: should we just temporarily remove Pesto, until the app store build has shipped, and then restore it?

[eseidelGoogle]

I'm fine with just turning it off and leaving in the sources for now. Unclear if we'll get back to it, but minesweeper and calculator are in a similar hidden-but-there state.

[HansMuller]

I'll remove it from the demo and tests.

[liyuqian]

@HansMuller : are there still issues on Pesto now? If not, I'd like to enable it in non-debug mode. Otherwise, people will probably complaint about the Pesto performance in debug mode (see #40042 (comment))...

[HansMuller]

I think it's OK to move Pesto back into the list of studies (for release mode). At least some of the issues are no longer causing problems: #7221, #6920, #5203, #5045, #5042

Some of the issues still persist: #5350, #4436.