Use float for scroll offset.

third_party/WebKit/LayoutTests/fast/css/zoom-body-scroll.html

Index: third_party/WebKit/LayoutTests/fast/css/zoom-body-scroll.html
diff --git a/third_party/WebKit/LayoutTests/fast/css/zoom-body-scroll.html b/third_party/WebKit/LayoutTests/fast/css/zoom-body-scroll.html
index 322427edd643b87892d163cb6a1ad12df328c6b5..dcb82ea9e1679a76bd2f827d8e7eecbc6b6d6b6a 100644
--- a/third_party/WebKit/LayoutTests/fast/css/zoom-body-scroll.html
+++ b/third_party/WebKit/LayoutTests/fast/css/zoom-body-scroll.html
@@ -24,16 +24,16 @@
             checkValue('document.scrollingElement.scrollHeight', 1000)
             checkValue('document.scrollingElement.scrollWidth', 1000);
 
-            // Scrolling right to 50.
-            document.scrollingElement.scrollLeft = 50;
-            checkValue('document.scrollingElement.scrollLeft', 50);
+            // Scrolling right to 40.
+            document.scrollingElement.scrollLeft = 40;
+            checkValue('document.scrollingElement.scrollLeft', 40);
 
             // Zooming in.
             eventSender.zoomPageIn();
             checkValue('document.scrollingElement.scrollHeight', 1000);
             checkValue('document.scrollingElement.scrollWidth', 1000);
             checkValue('document.scrollingElement.scrollTop', 0);
-            checkValue('document.scrollingElement.scrollLeft', 50);
+            checkValue('document.scrollingElement.scrollLeft', 40);
 
             // Scrolling down to 100.
             document.scrollingElement.scrollTop = 100;
@@ -42,7 +42,7 @@
             // Zooming back out.
             eventSender.zoomPageOut();
             checkValue('document.scrollingElement.scrollTop', 100);
-            checkValue('document.scrollingElement.scrollLeft', 50);
+            checkValue('document.scrollingElement.scrollLeft', 40);
         }
     </script>
 </body>