Pass only Uri to package:http APIs (#74285)

dev/benchmarks/test_apps/stocks/lib/stock_data.dart

@@ -68,9 +68,8 @@ class StockData extends ChangeNotifier {
   static const int _chunkCount = 30;
   int _nextChunk = 0;
 
-  String _urlToFetch(int chunk) {
-    return 'https://domokit.github.io/examples/stocks/data/stock_data_$chunk.json';
-  }
+  Uri _urlToFetch(int chunk) => Uri.https(
+      'domokit.github.io', 'examples/stocks/data/stock_data_$chunk.json');
 
   http.Client _httpClient;
 

dev/devicelab/lib/framework/cocoon.dart

@@ -170,7 +170,7 @@ class Cocoon {
 
   /// Make an API request to Cocoon.
   Future<Map<String, dynamic>> _sendCocoonRequest(String apiPath, [dynamic jsonData]) async {
-    final String url = '$baseCocoonApiUrl/$apiPath';
+    final Uri url = Uri.parse('$baseCocoonApiUrl/$apiPath');
 
     /// Retry requests to Cocoon as sometimes there are issues with the servers, such
     /// as version changes to the backend, datastore issues, or latency issues.

dev/tools/java_and_objc_doc.dart

@@ -28,7 +28,7 @@ Future<void> main(List<String> args) async {
 Future<Archive> fetchArchive(String url, int maxTries) async {
   List<int> responseBytes;
   for (int i = 0; i < maxTries; i++) {
-    final http.Response response = await http.get(url);
+    final http.Response response = await http.get(Uri.parse(url));
     if (response.statusCode == 200) {
       responseBytes = response.bodyBytes;
       break;

packages/flutter_tools/lib/src/devtools_launcher.dart

@@ -53,9 +53,9 @@ class DevtoolsServerLauncher extends DevtoolsLauncher {
       try {
         const String pubHostedUrlKey = 'PUB_HOSTED_URL';
         if (_platform.environment.containsKey(pubHostedUrlKey)) {
-          await http.head(_platform.environment[pubHostedUrlKey]);
+          await http.head(Uri.parse(_platform.environment[pubHostedUrlKey]));
         } else {
-          await http.head('https://pub.dev');
+          await http.head(Uri.https('pub.dev', ''));
         }
       } on Exception {
         offline = true;