Sanitize url refs in SVG attributes

Add some tests.
Sync with latest HTML5lib (includes above sanitization improvements).

vendor/plugins/HTML5lib/lib/html5/inputstream.rb

@@ -47,7 +47,7 @@ module HTML5
 
       #Encoding to use if no other information can be found
       @DEFAULT_ENCODING = 'windows-1252'
-    
+
       #Detect encoding iff no explicit "transport level" encoding is supplied
       if @encoding.nil? or not HTML5.is_valid_encoding(@encoding)
         @char_encoding = detect_encoding
@@ -235,14 +235,16 @@ module HTML5
     # Returns (line, col) of the current position in the stream.
     def position
       line, col = @line, @col
-      @queue.reverse.each do |c|
-        if c == "\n"
-          line -= 1
-          raise RuntimeError.new("col=#{col}") unless col == 0
-          col = @line_lengths[line]
-        else
-          col -= 1
-        end 
+      if @queue and @queue.last != :EOF
+        @queue.reverse.each do |c|
+          if c == "\n"
+            line -= 1
+            raise RuntimeError.new("col=#{col}") unless col == 0
+            col = @line_lengths[line]
+          else
+            col -= 1
+          end 
+        end
       end
       return [line + 1, col]
     end
@@ -434,7 +436,13 @@ module HTML5
         end
         break unless keep_parsing
       end
-      @encoding = @encoding.strip unless @encoding.nil?
+      unless @encoding.nil?
+        @encoding = @encoding.strip 
+        if ["UTF-16", "UTF-16BE", "UTF-16LE", "UTF-32", "UTF-32BE", "UTF-32LE"].include?(@encoding.upcase)
+          @encoding = 'utf-8'
+        end
+      end
+      
       return @encoding
     end