Clamp scrollX, scrollY, pageXOffset, and pageYOffset from double to int

tools/dom/templates/html/impl/impl_Window.darttemplate

Index: tools/dom/templates/html/impl/impl_Window.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_Window.darttemplate b/tools/dom/templates/html/impl/impl_Window.darttemplate
index 6b846f020420176217d48266485e2b3b59bfb01a..1c887777f862a644b825817c1cc583490ab3dcc3 100644
--- a/tools/dom/templates/html/impl/impl_Window.darttemplate
+++ b/tools/dom/templates/html/impl/impl_Window.darttemplate
@@ -254,6 +254,14 @@ $!MEMBERS
   }
 
 $if DART2JS
+  @DomName('Window.pageXOffset')
+  @DocsEditable()
+  int get pageXOffset => JS('num', '#.pageXOffset', this).round();
+
+  @DomName('Window.pageYOffset')
+  @DocsEditable()
+  int get pageYOffset => JS('num', '#.pageYOffset', this).round();
+
   /**
    * The distance this window has been scrolled horizontally.
    *
@@ -264,8 +272,11 @@ $if DART2JS
    * * [scrollX]
    * (https://developer.mozilla.org/en-US/docs/Web/API/Window.scrollX) from MDN.
    */
-  int get scrollX => JS('bool', '("scrollX" in #)', this) ? JS('int',
-      '#.scrollX', this) : document.documentElement.scrollLeft;
+  @DomName('Window.scrollX')
+  @DocsEditable()
+  int get scrollX => JS('bool', '("scrollX" in #)', this) ?
+      JS('num', '#.scrollX', this).round() :
+      document.documentElement.scrollLeft;
 
   /**
    * The distance this window has been scrolled vertically.
@@ -277,8 +288,27 @@ $if DART2JS
    * * [scrollY]
    * (https://developer.mozilla.org/en-US/docs/Web/API/Window.scrollY) from MDN.
    */
-  int get scrollY => JS('bool', '("scrollY" in #)', this) ? JS('int',
-      '#.scrollY', this) : document.documentElement.scrollTop;
+  @DomName('Window.scrollY')
+  @DocsEditable()
+  int get scrollY => JS('bool', '("scrollY" in #)', this) ?
+      JS('num', '#.scrollY', this).round() :
+      document.documentElement.scrollTop;
+$else
+  @DomName('Window.pageXOffset')
+  @DocsEditable()
+  int get pageXOffset => _blink.BlinkWindow.instance.pageXOffset_Getter_(this).round();
+
+  @DomName('Window.pageYOffset')
+  @DocsEditable()
+  int get pageYOffset => _blink.BlinkWindow.instance.pageYOffset_Getter_(this).round();
+
+  @DomName('Window.scrollX')
+  @DocsEditable()
+  int get scrollX => _blink.BlinkWindow.instance.scrollX_Getter_(this).round();
+
+  @DomName('Window.scrollY')
+  @DocsEditable()
+  int get scrollY => _blink.BlinkWindow.instance.scrollY_Getter_(this).round();
 $endif
 }