Fix XMLHttpRequest to set the responseType correctly

"xhr.responseType" was mis-spelled as "responsetype" (lowercase t)

Contributed by tbroyer
Fixes issue 7386
Review at https://gwt-code-reviews.appspot.com/1820806/

Review by: cromwellian@google.com

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@11264 8db76d5a-ed1c-0410-87a9-c151d255dfc7

user/src/com/google/gwt/xhr/client/XMLHttpRequest.java

diff --git a/user/src/com/google/gwt/xhr/client/XMLHttpRequest.java b/user/src/com/google/gwt/xhr/client/XMLHttpRequest.java
index 925c33a..d35d196 100644
--- a/user/src/com/google/gwt/xhr/client/XMLHttpRequest.java
+++ b/user/src/com/google/gwt/xhr/client/XMLHttpRequest.java
@@ -151,7 +151,7 @@
       }
     }
     if (xhr && responseType) {
-      xhr.responsetype = responseType;
+      xhr.responseType = responseType;
     }
     return xhr;
   }-*/;