[google_sign_in_ios] Upgrade GoogleSignIn iOS SDK to 7.1 (#6404)

1. Update GoogleSignIn iOS SDK dependency to [7.1](https://github.com/google/GoogleSignIn-iOS/releases/tag/7.1.0), which supports privacy manifests.
1. Update "fetch deps step" to run `pod repo update` every time to avoid missing spec failure. Also added a fetch deps step to the all_packages builds, since those could also use a `pod repo update` but I didn't want to add more logic to those bash scripts.
```
     [!] CocoaPods could not find compatible versions for pod "GoogleSignIn":
       In Podfile:
         google_sign_in_ios (from `Flutter/ephemeral/.symlinks/plugins/google_sign_in_ios/darwin`) was resolved to 0.0.1, which depends on
           GoogleSignIn (~> 7.1)
     None of your spec sources contain a spec satisfying the dependency: `GoogleSignIn (~> 7.1)`.
```
https://logs.chromium.org/logs/flutter/buildbucket/cr-buildbucket/8752192509749702705/+/u/Run_package_tests/download_Dart_and_iOS_deps/stdout

3. Looks like the new versions of [`GTMSessionFetcher`](https://github.com/CocoaPods/Specs/blob/master/Specs/c/e/3/GTMSessionFetcher/3.3.2/GTMSessionFetcher.podspec.json) and [`AppAuth`](https://github.com/CocoaPods/Specs/blob/master/Specs/b/b/9/AppAuth/1.7.3/AppAuth.podspec.json) don't define modules, so there's an error building it statically:
```
     [!] The following Swift pods cannot yet be integrated as static libraries:
     The Swift pod `GTMAppAuth` depends upon `GTMSessionFetcher` and `AppAuth`, which do not define modules. To opt into those targets generating module maps (which is necessary to import them from Swift when building as static libraries), you may set `use_modular_headers!` globally in your Podfile, or specify `:modular_headers => true` for particular dependencies.
```
I filed google/gtm-session-fetcher#384 and openid/AppAuth-iOS#844.

In the meantime, I updated the example apps to `use_frameworks!`, which would be on for Flutter Swift apps, but not Objective-C ones.  We could add something to the tool to detect this case, and suggest `use_frameworks!` be added?  

4.  Even though google_sign_in_ios does not contain Swift files, for some reason, there is a "pod lib lint" warning complaining `swift_version` isn't set. This seems related to `GTMAppAuth` dependency constraint that went from an Objective-C-only to Swift pod.  So I set `swift_version` since it's harmless.

```
- WARN  | swift: The validator used Swift `4.0` by default because no Swift version was specified. To specify a Swift version during validation, add the `swift_versions` attribute in your podspec. Note that usage of a `.swift-version` file is now deprecated.
```
https://logs.chromium.org/logs/flutter/buildbucket/cr-buildbucket/8752100979634945505/+/u/Run_package_tests/validate_iOS_and_macOS_podspecs/stdout

## Issues

* Fixes flutter/flutter#145777
* Fixes flutter/flutter#145866
* See also flutter/flutter#137140

.ci/targets/ios_build_all_packages.yaml

@@ -2,6 +2,10 @@ tasks:
   - name: prepare tool
     script: .ci/scripts/prepare_tool.sh
     infra_step: true # Note infra steps failing prevents "always" from running.
+  - name: download Dart and iOS deps
+    script: .ci/scripts/tool_runner.sh
+    args: ["fetch-deps", "--ios", "--supporting-target-platforms-only"]
+    infra_step: true
   - name: create all_packages app
     script: .ci/scripts/create_all_packages_app.sh
     infra_step: true # Note infra steps failing prevents "always" from running.

.ci/targets/macos_build_all_packages.yaml

@@ -2,6 +2,10 @@ tasks:
   - name: prepare tool
     script: .ci/scripts/prepare_tool.sh
     infra_step: true # Note infra steps failing prevents "always" from running.
+  - name: download Dart and macOS deps
+    script: .ci/scripts/tool_runner.sh
+    args: ["fetch-deps", "--macos", "--supporting-target-platforms-only"]
+    infra_step: true
   - name: create all_packages app
     script: .ci/scripts/create_all_packages_app.sh
     infra_step: true # Note infra steps failing prevents "always" from running.

packages/google_sign_in/google_sign_in_ios/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 5.7.6
+
+* Upgrades GoogleSignIn iOS SDK to 7.1.
+
 ## 5.7.5
 
 * Pins GoogleSignIn to iOS SDK "7.0.0" while preparing the update to 7.1.

packages/google_sign_in/google_sign_in_ios/darwin/google_sign_in_ios.podspec

@@ -15,12 +15,23 @@ Enables Google Sign-In in Flutter apps.
   s.source_files = 'Classes/**/*.{h,m}'
   s.public_header_files = 'Classes/**/*.h'
   s.module_map = 'Classes/FLTGoogleSignInPlugin.modulemap'
-  s.dependency 'GoogleSignIn', '~> 7.0.0'
+
+  # AppAuth and GTMSessionFetcher are GoogleSignIn transitive dependencies.
+  # Depend on versions which defines modules.
+  s.dependency 'AppAuth', '>= 1.7.4'
+  s.dependency 'GTMSessionFetcher', '>= 3.4.0'
+  s.dependency 'GoogleSignIn', '~> 7.1'
   s.static_framework = true
   s.ios.dependency 'Flutter'
   s.osx.dependency 'FlutterMacOS'
   s.ios.deployment_target = '12.0'
   s.osx.deployment_target = '10.15'
   s.pod_target_xcconfig = { 'DEFINES_MODULE' => 'YES' }
+
+  # google_sign_in_ios does not contain Swift files. For some reason, there
+  # is a "pod lib lint" warning unless swift_version is set. This seems related to
+  # GoogleSignIn depending a Swift pod (GTMAppAuth).
+  s.swift_version = '5.0'
+
   s.resource_bundles = {'google_sign_in_ios_privacy' => ['Resources/PrivacyInfo.xcprivacy']}
 end

packages/google_sign_in/google_sign_in_ios/example/ios/Runner.xcodeproj/project.pbxproj

@@ -273,7 +273,7 @@
 		97C146E61CF9000F007C117D /* Project object */ = {
 			isa = PBXProject;
 			attributes = {
-				LastUpgradeCheck = 1430;
+				LastUpgradeCheck = 1510;
 				ORGANIZATIONNAME = "The Flutter Authors";
 				TargetAttributes = {
 					97C146ED1CF9000F007C117D = {
@@ -386,11 +386,19 @@
 			);
 			inputPaths = (
 				"${PODS_ROOT}/Target Support Files/Pods-Runner/Pods-Runner-resources.sh",
+				"${PODS_CONFIGURATION_BUILD_DIR}/AppAuth/AppAuthCore_Privacy.bundle",
+				"${PODS_CONFIGURATION_BUILD_DIR}/GTMAppAuth/GTMAppAuth_Privacy.bundle",
+				"${PODS_CONFIGURATION_BUILD_DIR}/GTMSessionFetcher/GTMSessionFetcher_Core_Privacy.bundle",
+				"${PODS_CONFIGURATION_BUILD_DIR}/GTMSessionFetcher/GTMSessionFetcher_Full_Privacy.bundle",
 				"${PODS_CONFIGURATION_BUILD_DIR}/GoogleSignIn/GoogleSignIn.bundle",
 				"${PODS_CONFIGURATION_BUILD_DIR}/google_sign_in_ios/google_sign_in_ios_privacy.bundle",
 			);
 			name = "[CP] Copy Pods Resources";
 			outputPaths = (
+				"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/AppAuthCore_Privacy.bundle",
+				"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/GTMAppAuth_Privacy.bundle",
+				"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/GTMSessionFetcher_Core_Privacy.bundle",
+				"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/GTMSessionFetcher_Full_Privacy.bundle",
 				"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/GoogleSignIn.bundle",
 				"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}/google_sign_in_ios_privacy.bundle",
 			);

packages/google_sign_in/google_sign_in_ios/example/ios/Runner.xcodeproj/xcshareddata/xcschemes/Runner.xcscheme

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1430"
+   LastUpgradeVersion = "1510"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"

packages/google_sign_in/google_sign_in_ios/pubspec.yaml

@@ -2,7 +2,7 @@ name: google_sign_in_ios
 description: iOS implementation of the google_sign_in plugin.
 repository: https://github.com/flutter/packages/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: 5.7.5
+version: 5.7.6
 
 environment:
   sdk: ^3.2.3

script/tool/lib/src/fetch_deps_command.dart

@@ -11,6 +11,7 @@ import 'common/repository_package.dart';
 
 const int _exitPrecacheFailed = 3;
 const int _exitNothingRequested = 4;
+const int _exitPodUpdateFailed = 5;
 
 /// Download dependencies, both Dart and native.
 ///
@@ -79,22 +80,28 @@ class FetchDepsCommand extends PackageLoopingCommand {
     // `pod install` requires having the platform artifacts precached. See
     // https://github.com/flutter/flutter/blob/fb7a763c640d247d090cbb373e4b3a0459ac171b/packages/flutter_tools/bin/podhelper.rb#L47
     // https://github.com/flutter/flutter/blob/fb7a763c640d247d090cbb373e4b3a0459ac171b/packages/flutter_tools/bin/podhelper.rb#L130
-    if (getBoolArg(platformIOS)) {
-      final int exitCode = await processRunner.runAndStream(
+    final bool precacheIOS = getBoolArg(platformIOS);
+    final bool precacheMacOS = getBoolArg(platformMacOS);
+    if (precacheIOS || precacheMacOS) {
+      final int precacheExitCode = await processRunner.runAndStream(
         flutterCommand,
-        <String>['precache', '--ios'],
+        <String>[
+          'precache',
+          if (precacheIOS)
+            '--ios',
+          if (precacheMacOS)
+            '--macos',
+        ],
       );
-      if (exitCode != 0) {
+      if (precacheExitCode != 0) {
         throw ToolExit(_exitPrecacheFailed);
       }
-    }
-    if (getBoolArg(platformMacOS)) {
-      final int exitCode = await processRunner.runAndStream(
-        flutterCommand,
-        <String>['precache', '--macos'],
+      final int updateUpdateExitCode = await processRunner.runAndStream(
+        'pod',
+        <String>['repo', 'update'],
       );
-      if (exitCode != 0) {
-        throw ToolExit(_exitPrecacheFailed);
+      if (updateUpdateExitCode != 0) {
+        throw ToolExit(_exitPodUpdateFailed);
       }
     }
   }

script/tool/test/fetch_deps_command_test.dart

@@ -409,6 +409,11 @@ void main() {
               <String>['precache', '--ios'],
               null,
             ),
+            const ProcessCall(
+              'pod',
+              <String>['repo', 'update'],
+              null,
+            ),
             for (final Directory directory in exampleDirs)
               ProcessCall(
                 'flutter',
@@ -436,6 +441,7 @@ void main() {
                 .mockProcessesForExecutable[getFlutterCommand(mockPlatform)] =
             <FakeProcessInfo>[
           FakeProcessInfo(MockProcess(), <String>['precache']),
+          FakeProcessInfo(MockProcess(), <String>['repo', 'update']),
           FakeProcessInfo(MockProcess(exitCode: 1),
               <String>['build', 'ios', '--config-only']),
         ];
@@ -516,6 +522,11 @@ void main() {
               <String>['precache', '--macos'],
               null,
             ),
+            const ProcessCall(
+              'pod',
+              <String>['repo', 'update'],
+              null,
+            ),
             for (final Directory directory in exampleDirs)
               ProcessCall(
                 'flutter',
@@ -543,6 +554,7 @@ void main() {
                 .mockProcessesForExecutable[getFlutterCommand(mockPlatform)] =
             <FakeProcessInfo>[
           FakeProcessInfo(MockProcess(), <String>['precache']),
+          FakeProcessInfo(MockProcess(), <String>['repo', 'update']),
           FakeProcessInfo(MockProcess(exitCode: 1),
               <String>['build', 'macos', '--config-only']),
         ];