Update the gradle task to add fallback scheme and host if needed when retrieving deep links. (#146470)

This is to support feature:
https://github.com/flutter/devtools/issues/7541

before behavior: do not show this link in the dev tool if there's no
scheme or host
target behavior: show the link in the dev tool with a error text : (
missing scheme/ missing domain)



## Pre-launch Checklist

- [ ] 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], including [Features
we expect every widget to implement].
- [ ] I signed the [CLA].
- [ ] I listed at least one issue that this PR fixes in the description
above.
- [ ] I updated/added relevant documentation (doc comments with `///`).
- [ ] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [ ] All existing and new tests are passing.

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

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[Tree Hygiene]: https://github.com/flutter/flutter/wiki/Tree-hygiene
[test-exempt]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#tests
[Flutter Style Guide]:
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[Features we expect every widget to implement]:
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[breaking change policy]:
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[Data Driven Fixes]:
https://github.com/flutter/flutter/wiki/Data-driven-Fixes

packages/flutter_tools/gradle/src/main/groovy/flutter.groovy

@@ -570,11 +570,12 @@ class FlutterPlugin implements Plugin<Project> {
                                         }
                                     }
                                 }
-                                schemes.each { scheme ->
-                                    hosts.each { host ->
-                                        if (!paths) {
-                                            appLinkSettings.deeplinks.add(new Deeplink(scheme: scheme, host: host, path: ".*", intentFilterCheck: intentFilterCheck))
-                                        } else {
+                                if(!hosts.isEmpty() || !paths.isEmpty()){
+                                    if(schemes.isEmpty()){schemes.add(null)}
+                                    if(hosts.isEmpty()){hosts.add(null)}
+                                    if(paths.isEmpty()){paths.add('.*')}
+                                    schemes.each { scheme ->
+                                        hosts.each { host ->
                                             paths.each { path ->
                                                 appLinkSettings.deeplinks.add(new Deeplink(scheme: scheme, host: host, path: path, intentFilterCheck: intentFilterCheck))
                                             }

packages/flutter_tools/test/integration.shard/android_gradle_outputs_app_link_settings_test.dart

@@ -192,6 +192,55 @@ final XmlElement nonBrowsableCategoryIntentFilter = XmlElement(
     ),
   ],
 );
+final XmlElement nonSchemeCategoryIntentFilter = XmlElement(
+  XmlName('intent-filter'),
+  <XmlAttribute>[XmlAttribute(XmlName('autoVerify', 'android'), 'true')],
+  <XmlElement>[
+    XmlElement(
+      XmlName('action'),
+      <XmlAttribute>[XmlAttribute(XmlName('name', 'android'), 'android.intent.action.VIEW')],
+    ),
+    XmlElement(
+      XmlName('category'),
+      <XmlAttribute>[XmlAttribute(XmlName('name', 'android'), 'android.intent.category.DEFAULT')],
+    ),
+    XmlElement(
+      XmlName('category'),
+      <XmlAttribute>[XmlAttribute(XmlName('name', 'android'), 'android.intent.category.BROWSABLE')],
+    ),
+    XmlElement(
+      XmlName('data'),
+      <XmlAttribute>[
+        XmlAttribute(XmlName('host', 'android'), 'non-browsable-category.com'),
+      ],
+    ),
+  ],
+);
+final XmlElement nonHostCategoryIntentFilter = XmlElement(
+  XmlName('intent-filter'),
+  <XmlAttribute>[XmlAttribute(XmlName('autoVerify', 'android'), 'true')],
+  <XmlElement>[
+    XmlElement(
+      XmlName('action'),
+      <XmlAttribute>[XmlAttribute(XmlName('name', 'android'), 'android.intent.action.VIEW')],
+    ),
+    XmlElement(
+      XmlName('category'),
+      <XmlAttribute>[XmlAttribute(XmlName('name', 'android'), 'android.intent.category.DEFAULT')],
+    ),
+    XmlElement(
+      XmlName('category'),
+      <XmlAttribute>[XmlAttribute(XmlName('name', 'android'), 'android.intent.category.BROWSABLE')],
+    ),
+    XmlElement(
+      XmlName('data'),
+      <XmlAttribute>[
+        XmlAttribute(XmlName('scheme', 'android'), 'http'),
+        XmlAttribute(XmlName('path', 'android'), '/path1'),
+      ],
+    ),
+  ],
+);
 
 void main() {
   late Directory tempDir;
@@ -206,8 +255,8 @@ void main() {
 
   void testDeeplink(
     dynamic deeplink,
-    String scheme,
-    String host,
+    String? scheme,
+    String? host,
     String path, {
     required bool hasAutoVerify,
     required bool hasActionView,
@@ -251,6 +300,8 @@ void main() {
     activity.children.add(nonActionIntentFilter);
     activity.children.add(nonDefaultCategoryIntentFilter);
     activity.children.add(nonBrowsableCategoryIntentFilter);
+    activity.children.add(nonSchemeCategoryIntentFilter);
+    activity.children.add(nonHostCategoryIntentFilter);
     androidManifestFile.writeAsStringSync(androidManifest.toString(), flush: true);
 
     // Ensure that gradle files exists from templates.
@@ -278,7 +329,7 @@ void main() {
     expect(json['applicationId'], 'com.example.testapp');
     expect(json['deeplinkingFlagEnabled'], true);
     final List<dynamic> deeplinks = json['deeplinks']! as List<dynamic>;
-    expect(deeplinks.length, 8);
+    expect(deeplinks.length, 10);
     testDeeplink(deeplinks[0], 'http', 'pure-http.com', '.*', hasAutoVerify:true, hasActionView: true, hasDefaultCategory:true, hasBrowsableCategory: true);
     testDeeplink(deeplinks[1], 'custom', 'custom.com', '.*', hasAutoVerify:true, hasActionView: true, hasDefaultCategory:true, hasBrowsableCategory: true);
     testDeeplink(deeplinks[2], 'custom', 'hybrid.com', '.*', hasAutoVerify:true, hasActionView: true, hasDefaultCategory:true, hasBrowsableCategory: true);
@@ -287,6 +338,8 @@ void main() {
     testDeeplink(deeplinks[5], 'http', 'non-action.com', '.*', hasAutoVerify:true, hasActionView: false, hasDefaultCategory:true, hasBrowsableCategory: true);
     testDeeplink(deeplinks[6], 'http', 'non-default-category.com', '.*', hasAutoVerify:true, hasActionView: true, hasDefaultCategory:false, hasBrowsableCategory: true);
     testDeeplink(deeplinks[7], 'http', 'non-browsable-category.com', '.*', hasAutoVerify:true, hasActionView: true, hasDefaultCategory:true, hasBrowsableCategory: false);
+    testDeeplink(deeplinks[8], null, 'non-browsable-category.com', '.*', hasAutoVerify:true, hasActionView: true, hasDefaultCategory:true, hasBrowsableCategory: true);
+    testDeeplink(deeplinks[9], 'http', null, '/path1', hasAutoVerify:true, hasActionView: true, hasDefaultCategory:true, hasBrowsableCategory: true);
   });
 
   testWithoutContext(