Support launching a HTTPS URL (flutter#164720)

I setup a reverse proxy, but this piece of code only allows launching
HTTP URLs. I'm submitting a patch to fix the error.

See issue comment
Dart-Code/Dart-Code#5322 (comment)
for context.

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there for submitting PRs.
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responsibilities.
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we expect every widget to implement].
- [X] 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.

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Author: Wdestroier

packages/flutter_tools/lib/src/web/web_device.dart

@@ -116,8 +116,7 @@ abstract class ChromiumDevice extends Device {
     // for the web initialization and server logic.
     String url;
     if (debuggingOptions.webLaunchUrl != null) {
-      final pattern = RegExp(r'^((http)?:\/\/)[^\s]+');
-      if (pattern.hasMatch(debuggingOptions.webLaunchUrl!)) {
+      if (_isLaunchUrlValid(debuggingOptions.webLaunchUrl!)) {
         url = debuggingOptions.webLaunchUrl!;
       } else {
         throwToolExit('"${debuggingOptions.webLaunchUrl}" is not a valid HTTP URL.');
@@ -141,6 +140,11 @@ abstract class ChromiumDevice extends Device {
     return LaunchResult.succeeded(vmServiceUri: Uri.parse(url));
   }
 
+  bool _isLaunchUrlValid(String url) {
+    final pattern = RegExp(r'^(https?:\/\/)[^\s]+');
+    return pattern.hasMatch(url);
+  }
+
   @override
   Future<bool> stopApp(ApplicationPackage? app, {String? userIdentifier}) async {
     final Future<void>? future = _chrome?.close();

packages/flutter_tools/test/general.shard/web/devices_test.dart

@@ -12,6 +12,7 @@ import 'package:flutter_tools/src/build_info.dart';
 import 'package:flutter_tools/src/device.dart';
 import 'package:flutter_tools/src/web/chrome.dart';
 import 'package:flutter_tools/src/web/web_device.dart';
+import 'package:meta/meta.dart';
 import 'package:test/fake.dart';
 
 import '../../src/common.dart';
@@ -31,16 +32,20 @@ void main() {
     expect(await webDevices.pollingGetDevices(), isEmpty);
   });
 
+  _FakeChromiumDevice getFakeChromiumDevice() {
+    final launcher = TestChromiumLauncher(launcher: () => _OnceClosableChromium());
+
+    return _FakeChromiumDevice(
+      chromiumLauncher: launcher,
+      fileSystem: MemoryFileSystem.test(),
+      logger: BufferLogger.test(),
+    );
+  }
+
   testWithoutContext(
     'Successive calls of ChromiumDevice.stopApp() do not try to close chrome',
     () async {
-      final launcher = TestChromiumLauncher(launcher: () => _OnceClosableChromium());
-
-      final chromiumDevice = _FakeChromiumDevice(
-        chromiumLauncher: launcher,
-        fileSystem: MemoryFileSystem.test(),
-        logger: BufferLogger.test(),
-      );
+      final _FakeChromiumDevice chromiumDevice = getFakeChromiumDevice();
 
       await chromiumDevice.startApp(
         null,
@@ -379,6 +384,41 @@ void main() {
 
     expect((await macosWebDevices.pollingGetDevices()).whereType<MicrosoftEdgeDevice>(), isEmpty);
   });
+
+  @isTest
+  void testWebLaunchUrl(String description, {required String url, required Matcher matcher}) {
+    // ignore: unnecessary_parenthesis – Prevent IDEs from showing a run button.
+    (testWithoutContext)(description, () async {
+      final _FakeChromiumDevice chromiumDevice = getFakeChromiumDevice();
+
+      await expectLater(
+        () => chromiumDevice.startApp(
+          null,
+          debuggingOptions: DebuggingOptions.enabled(BuildInfo.debug, webLaunchUrl: url),
+          platformArgs: <String, Object?>{'uri': url},
+        ),
+        matcher,
+      );
+    });
+  }
+
+  testWebLaunchUrl(
+    'HTTP web launch url is not invalid',
+    url: 'http://localhost:3000',
+    matcher: returnsNormally,
+  );
+
+  testWebLaunchUrl(
+    'HTTPS web launch url is not invalid',
+    url: 'https://localhost:3000',
+    matcher: returnsNormally,
+  );
+
+  testWebLaunchUrl(
+    'Non-HTTP web launch url scheme is invalid',
+    url: 'file://path',
+    matcher: throwsToolExit(message: '"file://path" is not a valid HTTP URL.'),
+  );
 }
 
 /// A test implementation of the [ChromiumLauncher] that launches a fixed instance.