[maps] Use desaturated map tiles instead of bright map tiles by default

[nreese]

Fixes #115979

• Adds lightModeDefault to EMSTMSSourceDescriptor.
• EMSTMSSource.createDescriptor sets lightModeDefault to 'road_map_desaturated' for all newly created saved objects.
• Migration sets lightModeDefault to 'road_map' for saved objects created before 8.0.0 so there are no breaking changes and existing maps will still use bright tiles.

[elasticmachine]

Pinging @elastic/kibana-gis (Team:Geo)

[nreese]

@elasticmachine merge upstream

[nreese]

@elasticmachine merge upstream

[kibanamachine]

merge conflict between base and head

[nreese]

@elasticmachine merge upstream

[nickpeihl]

lgtm! tested in Chrome.

• New maps are by default desaturated
• Autoselect based on kibana theme still works
• Imported saved objects from older version (7.15.1) maintain their original layer style

[thomasneirynck]

+1 on code, some minor comments.

I don't feel strongly about this, but I think the initial app load looks "off".

before:

after:

I also wonder if any user has been truly disadvantaged by the current "bright" base-map as a default on startup.

Anyways, +1 on merging if there's an overall preference for this new base map. cc @jsanz @nickpeihl @ghudgins @miukimiu

[jsanz]

Tested in Chrome. Creating new maps and loading the sample datasets all come with the desaturated style. As @nickpeihl tested, importing the kibana sample flights saved object from a 7.15.0 instance keeps the original bright style.

I like this style as a default as it helps users focus on their data, as the basemap is usually here to provide spatial context.

[ghudgins]

❤️ i'm in agreement here as this gets out of the way of the data!

[thomasneirynck]

thx @ghudgins for weighing in, lgtm

[nreese]

@elasticmachine merge upstream

[nreese]

@elasticmachine merge upstream

[kibanamachine]

expected head sha didn’t match current head ref.

[kibanamachine]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: 118fe10
• Storybooks Preview

Test Failures

• [job] [logs] Default CI Group #12 / detection engine api security and spaces enabled Detection exceptions data types and operators Rule exception operators for data type keyword "is in list" operator will return 3 results if we have two lists with an AND keyword === "word one" AND keyword === "word two" since we have an array

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
maps	2.7MB	2.7MB	+114.0B

History

• 💔 Build #1954 failed 645ed9a
• 💔 Build #1922 failed 0880861
• 💚 Build #1853 succeeded a46dbfa
• 💔 Build #1794 failed 09298d3
• 💚 Build #1627 succeeded c67dc1a
• 💔 Build #1581 failed b892e57

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@elasticmachine merge upstream

[kibanamachine]

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