[google_sign_in] Adds support to send clientId as a parameter

[ggirotto]

This PR introduces the ability to send clientId as a parameter in google_sign_in plugin. It priorizes the parameterized clientId in iOS and Android platforms. If it wasn't send, then they try to fetch it from GoogleService-info.plist and google-services.json respectively.

List which issues are fixed by this PR. You must list at least one issue.

• #66005

Pre-launch Checklist

• The title of the PR starts with the name of the plugin surrounded by square brackets, e.g. [shared_preferences]
• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide and the C++, Objective-C, Java style guides.
• I listed at least one issue that this PR fixes in the description above.
• I added new tests to check the change I am making or feature I am adding, or Hixie said the PR is test exempt.
• I updated pubspec.yaml with an appropriate new version according to the pub versioning philosophy.
• I updated CHANGELOG.md to add a description of the change.
• I updated/added relevant documentation (doc comments with ///).
• I signed the CLA.
• All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel on Discord.

[ggirotto]

I'm not exactly sure how to update pubspec.yaml and CHANGELOG since the plugin is in the middle of a nullsafety pre-release

[stuartmorgan-g]

Thanks for the contribution! Looks like this is a pretty straightforward PR, so we can try to get it reviewed quickly. It will need tests though, per the contribution guidelines (you've checked the box, but there are no test files changed in the PR, so if there are test changes they were left out of the PR).

I'm not exactly sure how to update pubspec.yaml and CHANGELOG since the plugin is in the middle of a nullsafety pre-release

The release is now stable, so you can proceed here as normal once you merge in master.

[ggirotto]

@stuartmorgan I forgot to push my test commit. Now this PR should be complete

[cyanglaz]

=

[cyanglaz]

I think we also need to check [[call.arguments objectForKey:@"clientId"] isEqualTo:[NSNull null]]
Maybe refactor it out to a local bool var:

BOOL hasDynamicClientId = [[call.arguments objectForKey:@"clientId"] isKindOfClass:NSString.class]

[ggirotto]

You mean checking if clientId is a NSString object? Because ternary operator ?: will already check for nullability

[cyanglaz]

So we need to check != nil and != [NSNull null]
Checking is a NSString covers both cases.

[cyanglaz]

This change need to be published first.

[ggirotto]

@cyanglaz You mean in a separate PR? I can create a new one with only this change

[cyanglaz]

Yep, we need this in a separate PR and a version bump for the platform_interface. Then google_sign_in needs to dep on the new version.

[ggirotto]

@cyanglaz I created a new PR #3686. I didn't add any tests on it, since I suppose the current PR has the necessary tests to cover both PR changes

[cyanglaz]

I landed #3686. Once published, this PR should update the platform interface dependency to 2.0.1 .

[ggirotto]

@cyanglaz Updated and Rebased

[cyanglaz]

Looks like there's some issue with the format CI, could you fix it? The lint_darwin ci could be fixed by rebasing master I believe

[ggirotto]

@cyanglaz Formatting issues fixed and branched rebased master

[fluttergithubbot]

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[fluttergithubbot]

This pull request is not suitable for automatic merging in its current state.

• Please get at least one approved review before re-applying this label. Reviewers: If you left a comment approving, please use the "approve" review action instead.

[ggirotto]

@cyanglaz I don't understand the failing output from the CI build:

! webview_flutter 2.0.2 from path /tmp/cirrus-ci-build/packages/webview_flutter

! wifi_info_flutter 2.0.0 from path /tmp/cirrus-ci-build/packages/wifi_info_flutter/wifi_info_flutter

! wifi_info_flutter_platform_interface 2.0.1 from path /tmp/cirrus-ci-build/packages/wifi_info_flutter/wifi_info_flutter_platform_interface
Running "flutter pub get" in all_plugins...                         3.7s

Building without sound null safety
For more information see https://dart.dev/null-safety/unsound-null-safety

Building Linux application...                                   
CMake Error at /usr/share/cmake-3.16/Modules/FindPkgConfig.cmake:463 (message):

  A required package was not found

Call Stack (most recent call first):

  /usr/share/cmake-3.16/Modules/FindPkgConfig.cmake:643 (_pkg_check_modules_internal)

  flutter/CMakeLists.txt:29 (pkg_check_modules)

Could you help me understand what is going wrong here so I can fix it?

[stuartmorgan-g]

That failure is due to a change in Flutter itself; you'll need to merge master in again to pick up the corresponding fix in flutter/plugins.