Fix low risk nullable => non nullable change for NavigatorLanguage.language

third_party/WebKit/LayoutTests/fast/events/inputevents/inputevent-cut-paste.html

Index: third_party/WebKit/LayoutTests/fast/events/inputevents/inputevent-cut-paste.html
diff --git a/third_party/WebKit/LayoutTests/fast/events/inputevents/inputevent-cut-paste.html b/third_party/WebKit/LayoutTests/fast/events/inputevents/inputevent-cut-paste.html
index a656a5a9e7efe76509041fe65a23b7d2a322371c..3cdba2ba6937451666eb29a520c55d9ee628b9ed 100644
--- a/third_party/WebKit/LayoutTests/fast/events/inputevents/inputevent-cut-paste.html
+++ b/third_party/WebKit/LayoutTests/fast/events/inputevents/inputevent-cut-paste.html
@@ -40,7 +40,7 @@ test(function() {
     var lastPlainTextData = "";
     var lastHTMLData = "";
     editable.addEventListener('beforeinput', event => {
-        assert_equals(event.data, null, 'Cut&Paste should have null |data| field')
+        assert_equals(event.data, "", 'Cut&Paste should have empty plain text |data| field')

[foolip, 2016/12/15 10:53:49]

s/empty plain text/empty string/

(https://chromium.googlesource.com/chromium/src/+/master/docs/testing/writing_...
would suggest a description like "beforeinput event data attribute", but no need
to rewrite existing descriptions all over the place.)

         lastPlainTextData = event.dataTransfer ? event.dataTransfer.getData('text/plain') : null;
         lastHTMLData = event.dataTransfer ? event.dataTransfer.getData('text/html') : null;
     });