Revert 2 CLs to get one last Dartium 34.

tools/dom/idl/dart/dart.idl

Index: tools/dom/idl/dart/dart.idl
diff --git a/tools/dom/idl/dart/dart.idl b/tools/dom/idl/dart/dart.idl
index 6ef26f694da024e4f920bafd5d0581e51990dca4..7aa1b29e59d0b59f65008f96bf90b71950ef295f 100644
--- a/tools/dom/idl/dart/dart.idl
+++ b/tools/dom/idl/dart/dart.idl
@@ -35,8 +35,6 @@ interface Document {
 [Supplemental]
 interface Node {
   [Custom] Node cloneNode([Default=Undefined] optional boolean deep);
-  [Suppressed] readonly attribute Element nextElementSibling;
-  [Suppressed] readonly attribute Element previousElementSibling;
 };
 
 [Supplemental]
@@ -59,18 +57,6 @@ interface ElementTraversal : ChildNode, ParentNode {
 Element implements ElementTraversal;
 */
 
-[Supplemental]
-interface Element {
-  readonly attribute Element nextElementSibling;
-  readonly attribute Element previousElementSibling;
-};
-
-[Supplemental]
-interface CharacterData {
-  readonly attribute Element nextElementSibling;
-  readonly attribute Element previousElementSibling;
-};
-
 [Callback]
 interface TimeoutHandler {
   void handleEvent();
@@ -89,11 +75,6 @@ interface URL {
 interface CanvasRenderingContext2D {
   [DartName=createImageDataFromImageData] ImageData createImageData(ImageData imagedata);
 
-  // Removed in 1916.
-  [Suppressed] void drawSystemFocusRing(Element element);
-
-  [Suppressed] void assert(boolean condition);
-
   [Suppressed] attribute boolean webkitImageSmoothingEnabled;
 };
 
@@ -369,10 +350,4 @@ interface Window : EventTarget {};
 [Suppressed]
 interface Promise {};
 
-[Supplemental]
-interface Screen {
-    [Suppressed]
-    boolean lockOrientation(sequence<DOMString> orientations);
-};
-
 Element implements GlobalEventHandlers;