fix(package_info_plus): Added build signature to package info data

[acoutts]

Description

Re-submission from flutter/plugins#4013

This adds the android build signature to the package_info result. It returns an empty string on all other platforms.

For android this is useful when you need to get the SHA1 fingerprint which signed the current running app, for example when using platform-specific API keys for the Google Maps API where you must provide the signing certificate in a x-android-cert header.

Related Issues

flutter/flutter#83996

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[mhadaily]

Can you please merge with main

[acoutts]

@mhadaily you want me to merge this into the main on my fork?

[mhadaily]

yes, please on your fork, update main branch with upstream and then merge your branch with main so you get the latest updates from our main branch

[acoutts]

Done.

[mhadaily]

Thanks for the PR,

this seems to be valuable for Android only.

Let me ask @jpnurmi and @miquelbeltran about their opinion. What do you guys think about this PR?

[acoutts]

Thanks for the PR,

this seems to be valuable for Android only.

Let me ask @jpnurmi and @miquelbeltran about their opinion. What do you guys think about this PR?

I think it's valuable because of the use case I laid out - when using Google Maps, Google Place, and other APIs which use platform-specific API keys you need to send the build signature as a header. There are probably other use cases to have the build signature at runtime.

It seems like there might be other data that is platform specific people may want in the future. What about taking the approach of Device Info where they return platform data objects specific to each platform?

[miquelbeltran]

1. Fine for adding the SHA signature, although I had never the need for it
2. the changes on the iOS code must be removed
3. we need to be sure that all dependencies between the platform interface and platform implementation projects are updated correctly

[acoutts]

Just removed the inadvertent iOS changes.

[mhadaily]

LGTM ,thank you