Strip unused functionality from dart:html and fix strong mode errors. Switch from blacklisting pure…

tools/dom/templates/html/dart2js/html_dart2js.darttemplate

Index: tools/dom/templates/html/dart2js/html_dart2js.darttemplate
diff --git a/tools/dom/templates/html/dart2js/html_dart2js.darttemplate b/tools/dom/templates/html/dart2js/html_dart2js.darttemplate
index ead9d632d27d5aae1f7453178f221fec8447b8f9..a2bd1e8f02b2b37a7488bd6c4ba9f7f146d9857f 100644
--- a/tools/dom/templates/html/dart2js/html_dart2js.darttemplate
+++ b/tools/dom/templates/html/dart2js/html_dart2js.darttemplate
@@ -132,12 +132,6 @@ class HtmlElement extends Element {
   HtmlElement.created() : super.created();
 }
 
-// EntryArray type was removed, so explicitly adding it to allow support for
-// older Chrome versions.
-// Issue #12573.
-@Native("EntryArray")
-abstract class _EntryArray implements List<Entry> {}
-
 /**
  * Spawn a DOM isolate using the given URI in the same window.
  * This isolate is not concurrent.  It runs on the browser thread