Bug 1283803 - part4 : handle unicode \u0000 and \uFFFD. r=rillian

MozReview-Commit-ID: FtDPV9U7ffS

--HG--
extra : rebase_source : 787502b5cfccc216f7c6176a597aaf10fb3b5252

dom/media/webvtt/vtt.jsm

@@ -177,7 +177,7 @@ this.EXPORTED_SYMBOLS = ["WebVTT"];
                               "Malformed timestamp: " + oInput);
       }
       // Remove time stamp from input.
-      input = input.replace(/^[^\sa-zA-Z-]+/, "");
+      input = input.replace(/^[^\s\uFFFDa-zA-Z-]+/, "");
       return ts;
     }
 
@@ -1266,7 +1266,8 @@ this.EXPORTED_SYMBOLS = ["WebVTT"];
           ++pos;
         }
         self.buffer = buffer.substr(pos);
-        return line;
+        // Spec defined replacement.
+        return line.replace(/[\u0000]/g, "\uFFFD");
       }
 
       function createCueIfNeeded() {

testing/web-platform/meta/webvtt/webvtt-file-format-parsing/webvtt-file-parsing/001.html.ini

@@ -1,4 +0,0 @@
-[001.html]
-  type: testharness
-  [WebVTT parser tests, nulls.vtt]
-    expected: FAIL