Bug 1526749 - Drop Element.scrollByNoFlush. r=kats,mccr8

It's no longer used since bug 970125.

Differential Revision: https://phabricator.services.mozilla.com/D19289

--HG--
extra : moz-landing-system : lando

dom/base/Element.cpp

@@ -913,26 +913,6 @@ void Element::SetScrollLeft(int32_t aScrollLeft) {
   }
 }
 
-bool Element::ScrollByNoFlush(int32_t aDx, int32_t aDy) {
-  nsIScrollableFrame* sf = GetScrollFrame(nullptr, FlushType::None);
-  if (!sf) {
-    return false;
-  }
-
-  AutoWeakFrame weakRef(sf->GetScrolledFrame());
-
-  CSSIntPoint before = sf->GetScrollPositionCSSPixels();
-  sf->ScrollToCSSPixelsApproximate(CSSIntPoint(before.x + aDx, before.y + aDy));
-
-  // The frame was destroyed, can't keep on scrolling.
-  if (!weakRef.IsAlive()) {
-    return false;
-  }
-
-  CSSIntPoint after = sf->GetScrollPositionCSSPixels();
-  return (before != after);
-}
-
 void Element::MozScrollSnap() {
   nsIScrollableFrame* sf = GetScrollFrame(nullptr, FlushType::None);
   if (sf) {

dom/base/Element.h

@@ -1252,11 +1252,6 @@ class Element : public FragmentOrElement {
   MOZ_CAN_RUN_SCRIPT void ScrollTo(const ScrollToOptions& aOptions);
   MOZ_CAN_RUN_SCRIPT void ScrollBy(double aXScrollDif, double aYScrollDif);
   MOZ_CAN_RUN_SCRIPT void ScrollBy(const ScrollToOptions& aOptions);
-  /* Scrolls without flushing the layout.
-   * aDx is the x offset, aDy the y offset in CSS pixels.
-   * Returns true if we actually scrolled.
-   */
-  MOZ_CAN_RUN_SCRIPT bool ScrollByNoFlush(int32_t aDx, int32_t aDy);
   MOZ_CAN_RUN_SCRIPT int32_t ScrollTop();
   MOZ_CAN_RUN_SCRIPT void SetScrollTop(int32_t aScrollTop);
   MOZ_CAN_RUN_SCRIPT int32_t ScrollLeft();

dom/webidl/Element.webidl

@@ -147,13 +147,6 @@ interface Element : Node {
   [CEReactions, Throws]
   Attr? setAttributeNodeNS(Attr newAttr);
 
-  [ChromeOnly]
-  /**
-   * Scrolls the element by (dx, dy) CSS pixels without doing any
-   * layout flushing.
-   */
-  boolean scrollByNoFlush(long dx, long dy);
-
   [ChromeOnly]
   DOMMatrixReadOnly getTransformToAncestor(Element ancestor);
   [ChromeOnly]