Pass a Uri to package:http APIs (#2794)

Prepare for dart-lang/http#375

Author: natebosch

lib/src/command/lish.dart

@@ -96,7 +96,8 @@ class LishCommand extends PubCommand {
 
           var location = postResponse.headers['location'];
           if (location == null) throw PubHttpException(postResponse);
-          handleJsonSuccess(await client.get(location, headers: pubApiHeaders));
+          handleJsonSuccess(
+              await client.get(Uri.parse(location), headers: pubApiHeaders));
         });
       });
     } on PubHttpException catch (error) {

lib/src/command/login.dart

@@ -40,8 +40,8 @@ class LoginCommand extends PubCommand {
 
   Future<_UserInfo> retrieveUserInfo() async {
     return await oauth2.withClient(cache, (client) async {
-      final discovery = await httpClient
-          .get('https://accounts.google.com/.well-known/openid-configuration');
+      final discovery = await httpClient.get(Uri.https(
+          'accounts.google.com', '/.well-known/openid-configuration'));
       final userInfoEndpoint = json.decode(discovery.body)['userinfo_endpoint'];
       final userInfoRequest = await client.get(userInfoEndpoint);
       if (userInfoRequest.statusCode != 200) return null;