Check the state of the HTTP request and response when handling headers

runtime/bin/http.dart

Index: runtime/bin/http.dart
diff --git a/runtime/bin/http.dart b/runtime/bin/http.dart
index c90e8b2823d057944fb7d5f457ba9f21978b1cc8..176ccf5bf91fc6fe2a83fa7fc3694b07def0aac5 100644
--- a/runtime/bin/http.dart
+++ b/runtime/bin/http.dart
@@ -416,12 +416,16 @@ interface HttpClient default _HttpClient {
   HttpClientConnection openUrl(String method, Uri url);
 
   /**
-   * Opens a HTTP connection using the GET method. See [open] for details.
+   * Opens a HTTP connection using the GET method. See [open] for
+   * details. Using this method to open a HTTP connection will set the
+   * content length to 0.
    */
   HttpClientConnection get(String host, int port, String path);
 
   /**
-   * Opens a HTTP connection using the GET method. See [openUrl] for details.
+   * Opens a HTTP connection using the GET method. See [openUrl] for
+   * details. Using this method to open a HTTP connection will set the
+   * content length to 0.
    */
   HttpClientConnection getUrl(Uri url);