Revert "Flipping the direction of WheelEvent.deltaX/Y to follow standards"

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

Index: tools/dom/templates/html/impl/impl_WheelEvent.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_WheelEvent.darttemplate b/tools/dom/templates/html/impl/impl_WheelEvent.darttemplate
index 3676dd896e03d9b0f50692d3ebe7f101cd06cf0d..93da12737b89fb857bb4f42dff7ce764a8122475 100644
--- a/tools/dom/templates/html/impl/impl_WheelEvent.darttemplate
+++ b/tools/dom/templates/html/impl/impl_WheelEvent.darttemplate
@@ -22,13 +22,6 @@ $(ANNOTATIONS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
     }
     final event = document.$dom_createEvent(eventType);
 $if DART2JS
-    // If polyfilling, then flip these because we'll flip them back to match
-    // the W3C standard:
-    // http://dev.w3.org/2006/webapi/DOM-Level-3-Events/html/DOM3-Events.html#events-WheelEvent-deltaY
-    if (JS('bool', '#.deltaY === undefined', event)) {
-      deltaX = -deltaX;
-      deltaY = -deltaY;
-    }
     if (event._hasInitWheelEvent) {
       var modifiers = [];
       if (ctrlKey) {
@@ -83,14 +76,6 @@ $endif
 $!MEMBERS
 
 $if DART2JS
-  /**
-   * The amount that is expected to scroll vertically, in units determined by
-   * [deltaMode].
-   *
-   * See also:
-   *
-   * * [WheelEvent.deltaY](http://dev.w3.org/2006/webapi/DOM-Level-3-Events/html/DOM3-Events.html#events-WheelEvent-deltaY) from the W3C.
-   */
   @DomName('WheelEvent.deltaY')
   num get deltaY {
     if (JS('bool', '#.deltaY !== undefined', this)) {
@@ -98,7 +83,7 @@ $if DART2JS
       return this._deltaY;
     } else if (JS('bool', '#.wheelDelta !== undefined', this)) {
       // Chrome and IE
-      return -this._wheelDelta;
+      return this._wheelDelta;
     } else if (JS('bool', '#.detail !== undefined', this)) {
       // Firefox
 
@@ -109,9 +94,9 @@ $if DART2JS
         // Firefox is normally the number of lines to scale (normally 3)
         // so multiply it by 40 to get pixels to move, matching IE & WebKit.
         if (detail < 100) {
-          return -detail * 40;
+          return detail * 40;
         }
-        return -detail;
+        return detail;
       }
       return 0;
     }
@@ -119,14 +104,6 @@ $if DART2JS
         'deltaY is not supported');
   }
 
-  /**
-   * The amount that is expected to scroll horizontally, in units determined by
-   * [deltaMode].
-   *
-   * See also:
-   *
-   * * [WheelEvent.deltaX](http://dev.w3.org/2006/webapi/DOM-Level-3-Events/html/DOM3-Events.html#events-WheelEvent-deltaX) from the W3C.
-   */
   @DomName('WheelEvent.deltaX')
   num get deltaX {
     if (JS('bool', '#.deltaX !== undefined', this)) {
@@ -134,7 +111,7 @@ $if DART2JS
       return this._deltaX;
     } else if (JS('bool', '#.wheelDeltaX !== undefined', this)) {
       // Chrome
-      return -this._wheelDeltaX;
+      return this._wheelDeltaX;
     } else if (JS('bool', '#.detail !== undefined', this)) {
       // Firefox and IE.
       // IE will have detail set but will not set axis.
@@ -147,9 +124,9 @@ $if DART2JS
         // Firefox is normally the number of lines to scale (normally 3)
         // so multiply it by 40 to get pixels to move, matching IE & WebKit.
         if (detail < 100) {
-          return -detail * 40;
+          return detail * 40;
         }
-        return -detail;
+        return detail;
       }
       return 0;
     }
@@ -216,26 +193,9 @@ $if DART2JS
       int deltaMode) native;
 
 $else
-  /**
-   * The amount that is expected to scroll horizontally, in units determined by
-   * [deltaMode].
-   *
-   * See also:
-   *
-   * * [WheelEvent.deltaX](http://dev.w3.org/2006/webapi/DOM-Level-3-Events/html/DOM3-Events.html#events-WheelEvent-deltaX) from the W3C.
-   */
   @DomName('WheelEvent.deltaX')
-  num get deltaX => -$dom_wheelDeltaX;
-
-  /**
-   * The amount that is expected to scroll vertically, in units determined by
-   * [deltaMode].
-   *
-   * See also:
-   *
-   * * [WheelEvent.deltaY](http://dev.w3.org/2006/webapi/DOM-Level-3-Events/html/DOM3-Events.html#events-WheelEvent-deltaY) from the W3C.
-   */
+  num get deltaX => $dom_wheelDeltaX;
   @DomName('WheelEvent.deltaY')
-  num get deltaY => -$dom_wheelDeltaY;
+  num get deltaY => $dom_wheelDeltaY;
 $endif
 }