[google_sign_in] Correctly passes `serverClientId` to native libs (#6691)

* Correctly passes serverClientId to native libs

* Bumps versions
diff --git a/packages/google_sign_in/google_sign_in_android/CHANGELOG.md b/packages/google_sign_in/google_sign_in_android/CHANGELOG.md
index 342166a..bb54cf4 100644
--- a/packages/google_sign_in/google_sign_in_android/CHANGELOG.md
+++ b/packages/google_sign_in/google_sign_in_android/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 6.1.2
+
+* Fixes passing `serverClientId` via the channelled `init` call
+
 ## 6.1.1
 
 * Corrects typos in plugin error logs and removes not actionable warnings.
diff --git a/packages/google_sign_in/google_sign_in_android/lib/google_sign_in_android.dart b/packages/google_sign_in/google_sign_in_android/lib/google_sign_in_android.dart
index 731da39..5a2ccab 100644
--- a/packages/google_sign_in/google_sign_in_android/lib/google_sign_in_android.dart
+++ b/packages/google_sign_in/google_sign_in_android/lib/google_sign_in_android.dart
@@ -45,6 +45,7 @@
       'scopes': params.scopes,
       'hostedDomain': params.hostedDomain,
       'clientId': params.clientId,
+      'serverClientId': params.serverClientId,
       'forceCodeForRefreshToken': params.forceCodeForRefreshToken,
     });
   }
diff --git a/packages/google_sign_in/google_sign_in_android/pubspec.yaml b/packages/google_sign_in/google_sign_in_android/pubspec.yaml
index 086a151..4427db0 100644
--- a/packages/google_sign_in/google_sign_in_android/pubspec.yaml
+++ b/packages/google_sign_in/google_sign_in_android/pubspec.yaml
@@ -2,7 +2,7 @@
 description: Android implementation of the google_sign_in plugin.
 repository: https://github.com/flutter/plugins/tree/main/packages/google_sign_in/google_sign_in_android
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+google_sign_in%22
-version: 6.1.1
+version: 6.1.2
 
 environment:
   sdk: ">=2.14.0 <3.0.0"
diff --git a/packages/google_sign_in/google_sign_in_android/test/google_sign_in_android_test.dart b/packages/google_sign_in/google_sign_in_android/test/google_sign_in_android_test.dart
index 948ced3..c081418 100644
--- a/packages/google_sign_in/google_sign_in_android/test/google_sign_in_android_test.dart
+++ b/packages/google_sign_in/google_sign_in_android/test/google_sign_in_android_test.dart
@@ -111,6 +111,7 @@
         'scopes': <String>['two', 'scopes'],
         'signInOption': 'SignInOption.games',
         'clientId': 'fakeClientId',
+        'serverClientId': null,
         'forceCodeForRefreshToken': false,
       }),
       () {
@@ -119,12 +120,14 @@
             scopes: <String>['two', 'scopes'],
             signInOption: SignInOption.games,
             clientId: 'fakeClientId',
+            serverClientId: 'fakeServerClientId',
             forceCodeForRefreshToken: true));
       }: isMethodCall('init', arguments: <String, dynamic>{
         'hostedDomain': 'example.com',
         'scopes': <String>['two', 'scopes'],
         'signInOption': 'SignInOption.games',
         'clientId': 'fakeClientId',
+        'serverClientId': 'fakeServerClientId',
         'forceCodeForRefreshToken': true,
       }),
       () {
diff --git a/packages/google_sign_in/google_sign_in_ios/CHANGELOG.md b/packages/google_sign_in/google_sign_in_ios/CHANGELOG.md
index ecb3b6b..7c5ebc0 100644
--- a/packages/google_sign_in/google_sign_in_ios/CHANGELOG.md
+++ b/packages/google_sign_in/google_sign_in_ios/CHANGELOG.md
@@ -1,5 +1,6 @@
-## NEXT
+## 5.5.1
 
+* Fixes passing `serverClientId` via the channelled `init` call
 * Updates minimum Flutter version to 2.10.
 
 ## 5.5.0
diff --git a/packages/google_sign_in/google_sign_in_ios/lib/google_sign_in_ios.dart b/packages/google_sign_in/google_sign_in_ios/lib/google_sign_in_ios.dart
index 07407ea..d7b6f79 100644
--- a/packages/google_sign_in/google_sign_in_ios/lib/google_sign_in_ios.dart
+++ b/packages/google_sign_in/google_sign_in_ios/lib/google_sign_in_ios.dart
@@ -49,6 +49,7 @@
       'scopes': params.scopes,
       'hostedDomain': params.hostedDomain,
       'clientId': params.clientId,
+      'serverClientId': params.serverClientId,
     });
   }
 
diff --git a/packages/google_sign_in/google_sign_in_ios/pubspec.yaml b/packages/google_sign_in/google_sign_in_ios/pubspec.yaml
index 24c08cd..04998d8 100644
--- a/packages/google_sign_in/google_sign_in_ios/pubspec.yaml
+++ b/packages/google_sign_in/google_sign_in_ios/pubspec.yaml
@@ -2,7 +2,7 @@
 description: iOS implementation of the google_sign_in plugin.
 repository: https://github.com/flutter/plugins/tree/main/packages/google_sign_in/google_sign_in_ios
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+google_sign_in%22
-version: 5.5.0
+version: 5.5.1
 
 environment:
   sdk: ">=2.14.0 <3.0.0"
diff --git a/packages/google_sign_in/google_sign_in_ios/test/google_sign_in_ios_test.dart b/packages/google_sign_in/google_sign_in_ios/test/google_sign_in_ios_test.dart
index ace6509..4584298 100644
--- a/packages/google_sign_in/google_sign_in_ios/test/google_sign_in_ios_test.dart
+++ b/packages/google_sign_in/google_sign_in_ios/test/google_sign_in_ios_test.dart
@@ -124,16 +124,19 @@
         'hostedDomain': 'example.com',
         'scopes': <String>['two', 'scopes'],
         'clientId': 'fakeClientId',
+        'serverClientId': null,
       }),
       () {
         googleSignIn.initWithParams(const SignInInitParameters(
             hostedDomain: 'example.com',
             scopes: <String>['two', 'scopes'],
-            clientId: 'fakeClientId'));
+            clientId: 'fakeClientId',
+            serverClientId: 'fakeServerClientId'));
       }: isMethodCall('init', arguments: <String, dynamic>{
         'hostedDomain': 'example.com',
         'scopes': <String>['two', 'scopes'],
         'clientId': 'fakeClientId',
+        'serverClientId': 'fakeServerClientId',
       }),
       () {
         googleSignIn.getTokens(