Remove doc for --ignore-deprecation and check for pubspec before v1 embedding check (#108523)

packages/flutter_tools/lib/src/project.dart

@@ -377,7 +377,7 @@ class FlutterProject {
   }
 
   void checkForDeprecation({DeprecationBehavior deprecationBehavior = DeprecationBehavior.none}) {
-    if (android.existsSync()) {
+    if (android.existsSync() && pubspecFile.existsSync()) {
       android.checkForDeprecation(deprecationBehavior: deprecationBehavior);
     }
   }
@@ -599,14 +599,11 @@ class AndroidProject extends FlutterProjectPlatform {
 Warning
 ──────────────────────────────────────────────────────────────────────────────
 Your Flutter application is created using an older version of the Android
-embedding. It is being deprecated in favor of Android embedding v2. Follow the
-steps at
+embedding. It is being deprecated in favor of Android embedding v2. To migrate
+your project, follow the steps at:
 
 https://github.com/flutter/flutter/wiki/Upgrading-pre-1.12-Android-projects
 
-to migrate your project. You may also pass the --ignore-deprecation flag to
-ignore this check and continue with the deprecated v1 embedding. However,
-the v1 Android embedding will be removed in future versions of Flutter.
 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
 The detected reason was:
 

packages/flutter_tools/test/general.shard/project_test.dart

@@ -191,7 +191,7 @@ void main() {
       _testInMemory('checkForDeprecation fails on invalid android app manifest file', () async {
         // This is not a valid Xml document
         const String invalidManifest = '<manifest></application>';
-        final FlutterProject project = await someProject(androidManifestOverride: invalidManifest);
+        final FlutterProject project = await someProject(androidManifestOverride: invalidManifest, includePubspec: true);
 
         expect(
           () => project.checkForDeprecation(deprecationBehavior: DeprecationBehavior.ignore),
@@ -199,7 +199,7 @@ void main() {
         );
       });
       _testInMemory('Android project not on v2 embedding shows a warning', () async {
-        final FlutterProject project = await someProject();
+        final FlutterProject project = await someProject(includePubspec: true);
         // The default someProject with an empty <manifest> already indicates
         // v1 embedding, as opposed to having <meta-data
         // android:name="flutterEmbedding" android:value="2" />.
@@ -208,7 +208,7 @@ void main() {
         expect(testLogger.statusText, contains('https://github.com/flutter/flutter/wiki/Upgrading-pre-1.12-Android-projects'));
       });
       _testInMemory('Android project not on v2 embedding exits', () async {
-        final FlutterProject project = await someProject();
+        final FlutterProject project = await someProject(includePubspec: true);
         // The default someProject with an empty <manifest> already indicates
         // v1 embedding, as opposed to having <meta-data
         // android:name="flutterEmbedding" android:value="2" />.
@@ -221,7 +221,7 @@ void main() {
         expect(testLogger.statusText, contains('No `<meta-data android:name="flutterEmbedding" android:value="2"/>` in '));
       });
       _testInMemory('Project not on v2 embedding does not warn if deprecation status is irrelevant', () async {
-        final FlutterProject project = await someProject();
+        final FlutterProject project = await someProject(includePubspec: true);
         // The default someProject with an empty <manifest> already indicates
         // v1 embedding, as opposed to having <meta-data
         // android:name="flutterEmbedding" android:value="2" />.
@@ -230,7 +230,7 @@ void main() {
         expect(testLogger.statusText, isEmpty);
       });
       _testInMemory('Android project not on v2 embedding ignore continues', () async {
-        final FlutterProject project = await someProject();
+        final FlutterProject project = await someProject(includePubspec: true);
         // The default someProject with an empty <manifest> already indicates
         // v1 embedding, as opposed to having <meta-data
         // android:name="flutterEmbedding" android:value="2" />.
@@ -238,6 +238,15 @@ void main() {
         project.checkForDeprecation(deprecationBehavior: DeprecationBehavior.ignore);
         expect(testLogger.statusText, contains('https://github.com/flutter/flutter/wiki/Upgrading-pre-1.12-Android-projects'));
       });
+      _testInMemory('Android project no pubspec continues', () async {
+        final FlutterProject project = await someProject();
+        // The default someProject with an empty <manifest> already indicates
+        // v1 embedding, as opposed to having <meta-data
+        // android:name="flutterEmbedding" android:value="2" />.
+
+        project.checkForDeprecation(deprecationBehavior: DeprecationBehavior.ignore);
+        expect(testLogger.statusText, isNot(contains('https://github.com/flutter/flutter/wiki/Upgrading-pre-1.12-Android-projects')));
+      });
       _testInMemory('Android plugin project does not throw v1 embedding deprecation warning', () async {
         final FlutterProject project = await aPluginProject();
 
@@ -781,12 +790,18 @@ apply plugin: 'kotlin-android'
 
 Future<FlutterProject> someProject({
   String androidManifestOverride,
+  bool includePubspec = false,
 }) async {
   final Directory directory = globals.fs.directory('some_project');
   directory.childDirectory('.dart_tool')
     .childFile('package_config.json')
     ..createSync(recursive: true)
     ..writeAsStringSync('{"configVersion":2,"packages":[]}');
+  if (includePubspec) {
+    directory.childFile('pubspec.yaml')
+    ..createSync(recursive: true)
+    ..writeAsStringSync(validPubspec);
+  }
   directory.childDirectory('ios').createSync(recursive: true);
   final Directory androidDirectory = directory
       .childDirectory('android')