Bug 539331 - browser_sanitizeDialog.js is failing, r=matspal

content/events/src/nsEventStateManager.cpp

@@ -2656,16 +2656,16 @@ nsEventStateManager::DecideGestureEvent(nsGestureNotifyEvent* aEvent,
           displayPanFeedback = PR_FALSE;
         }
       } else { //Not a XUL box
-        nsMargin scrollbarSizes = scrollableFrame->GetActualScrollbarSizes();
+        PRUint32 scrollbarVisibility = scrollableFrame->GetScrollbarVisibility();
 
         //Check if we have visible scrollbars
-        if (scrollbarSizes.LeftRight()) {
+        if (scrollbarVisibility & nsIScrollableFrame::VERTICAL) {
           panDirection = nsGestureNotifyEvent::ePanVertical;
           displayPanFeedback = PR_TRUE;
           break;
         }
 
-        if (scrollbarSizes.TopBottom()) {
+        if (scrollbarVisibility & nsIScrollableFrame::HORIZONTAL) {
           panDirection = nsGestureNotifyEvent::ePanHorizontal;
           displayPanFeedback = PR_TRUE;
         }

docshell/base/nsDocShell.cpp

@@ -4811,11 +4811,11 @@ nsDocShell::GetScrollbarVisibility(PRBool * verticalVisible,
     nsIScrollableFrame* sf = GetRootScrollFrame();
     NS_ENSURE_TRUE(sf, NS_ERROR_FAILURE);
 
-    nsMargin scrollbars = sf->GetActualScrollbarSizes();
+    PRUint32 scrollbarVisibility = sf->GetScrollbarVisibility();
     if (verticalVisible)
-        *verticalVisible = scrollbars.left != 0 || scrollbars.right != 0;
+        *verticalVisible = (scrollbarVisibility & nsIScrollableFrame::VERTICAL) != 0;
     if (horizontalVisible)
-        *horizontalVisible = scrollbars.top != 0 || scrollbars.bottom != 0;
+        *horizontalVisible = (scrollbarVisibility & nsIScrollableFrame::HORIZONTAL) != 0;
 
     return NS_OK;
 }

layout/base/nsLayoutUtils.cpp

@@ -679,15 +679,17 @@ nsLayoutUtils::GetNearestScrollableFrameForDirection(nsIFrame* aFrame,
     nsIScrollableFrame* scrollableFrame = do_QueryFrame(f);
     if (scrollableFrame) {
       nsPresContext::ScrollbarStyles ss = scrollableFrame->GetScrollbarStyles();
-      nsMargin scrollbarSizes = scrollableFrame->GetActualScrollbarSizes();
+      PRUint32 scrollbarVisibility = scrollableFrame->GetScrollbarVisibility();
       nsRect scrollRange = scrollableFrame->GetScrollRange();
       // Require visible scrollbars or something to scroll to in
       // the given direction.
       if (aDirection == eVertical ?
           (ss.mVertical != NS_STYLE_OVERFLOW_HIDDEN &&
-           (scrollbarSizes.LeftRight() || scrollRange.height > 0)) :
+           ((scrollbarVisibility & nsIScrollableFrame::VERTICAL) ||
+            scrollRange.height > 0)) :
           (ss.mHorizontal != NS_STYLE_OVERFLOW_HIDDEN &&
-           (scrollbarSizes.TopBottom() || scrollRange.width > 0)))
+           ((scrollbarVisibility & nsIScrollableFrame::HORIZONTAL) ||
+            scrollRange.width > 0)))
         return scrollableFrame;
     }
   }

layout/generic/nsFrame.cpp

@@ -5985,13 +5985,10 @@ nsIFrame::IsFocusable(PRInt32 *aTabIndex, PRBool aWithMouse)
         // When clicked on, the selection position within the element 
         // will be enough to make them keyboard scrollable.
         nsIScrollableFrame *scrollFrame = do_QueryFrame(this);
-        if (scrollFrame) {
-          nsMargin margin = scrollFrame->GetActualScrollbarSizes();
-          if (margin.top || margin.right || margin.bottom || margin.left) {
-            // Scroll bars will be used for overflow
-            isFocusable = PR_TRUE;
-            tabIndex = 0;
-          }
+        if (scrollFrame && scrollFrame->GetScrollbarVisibility() != 0) {
+          // Scroll bars will be used for overflow
+          isFocusable = PR_TRUE;
+          tabIndex = 0;
         }
       }
     }

layout/generic/nsGfxScrollFrame.cpp

@@ -485,10 +485,21 @@ nsHTMLScrollFrame::ReflowScrolledFrame(ScrollReflowState* aState,
   kidReflowState.mComputedMinHeight = computedMinHeight;
   kidReflowState.mComputedMaxHeight = computedMaxHeight;
 
+  // Temporarily set mHasHorizontalScrollbar/mHasVerticalScrollbar to
+  // reflect our assumptions while we reflow the child.
+  PRBool didHaveHorizonalScrollbar = mInner.mHasHorizontalScrollbar;
+  PRBool didHaveVerticalScrollbar = mInner.mHasVerticalScrollbar;
+  mInner.mHasHorizontalScrollbar = aAssumeHScroll;
+  mInner.mHasVerticalScrollbar = aAssumeVScroll;
+
   nsReflowStatus status;
   nsresult rv = ReflowChild(mInner.mScrolledFrame, presContext, *aMetrics,
                             kidReflowState, 0, 0,
                             NS_FRAME_NO_MOVE_FRAME | NS_FRAME_NO_MOVE_VIEW, status);
+
+  mInner.mHasHorizontalScrollbar = didHaveHorizonalScrollbar;
+  mInner.mHasVerticalScrollbar = didHaveVerticalScrollbar;
+
   // Don't resize or position the view (if any) because we're going to resize
   // it to the correct size anyway in PlaceScrollArea. Allowing it to
   // resize here would size it to the natural height of the frame,

layout/generic/nsGfxScrollFrame.h

@@ -206,6 +206,10 @@ public:
   nsRect GetScrolledRectInternal(const nsRect& aScrolledOverflowArea,
                                  const nsSize& aScrollPortSize) const;
 
+  PRUint32 GetScrollbarVisibility() const {
+    return (mHasVerticalScrollbar ? nsIScrollableFrame::VERTICAL : 0) |
+           (mHasHorizontalScrollbar ? nsIScrollableFrame::HORIZONTAL : 0);
+  }
   nsMargin GetActualScrollbarSizes() const;
   nsMargin GetDesiredScrollbarSizes(nsBoxLayoutState* aState);
   PRBool IsLTR() const;
@@ -376,6 +380,9 @@ public:
   virtual nsGfxScrollFrameInner::ScrollbarStyles GetScrollbarStyles() const {
     return mInner.GetScrollbarStylesFromFrame();
   }
+  virtual PRUint32 GetScrollbarVisibility() const {
+    return mInner.GetScrollbarVisibility();
+  }
   virtual nsMargin GetActualScrollbarSizes() const {
     return mInner.GetActualScrollbarSizes();
   }
@@ -598,6 +605,9 @@ public:
   virtual nsGfxScrollFrameInner::ScrollbarStyles GetScrollbarStyles() const {
     return mInner.GetScrollbarStylesFromFrame();
   }
+  virtual PRUint32 GetScrollbarVisibility() const {
+    return mInner.GetScrollbarVisibility();
+  }
   virtual nsMargin GetActualScrollbarSizes() const {
     return mInner.GetActualScrollbarSizes();
   }

layout/generic/nsIScrollableFrame.h

@@ -74,6 +74,13 @@ public:
    */
   virtual ScrollbarStyles GetScrollbarStyles() const = 0;
 
+  enum { HORIZONTAL = 0x01, VERTICAL = 0x02 };
+  /**
+   * Return the scrollbars which are visible. It's OK to call this during reflow
+   * of the scrolled contents, in which case it will reflect the current
+   * assumptions about scrollbar visibility.
+   */
+  virtual PRUint32 GetScrollbarVisibility() const = 0;
   /**
    * Return the actual sizes of all possible scrollbars. Returns 0 for scrollbar
    * positions that don't have a scrollbar or where the scrollbar is not visible.
@@ -83,12 +90,14 @@ public:
   virtual nsMargin GetActualScrollbarSizes() const = 0;
   /**
    * Return the sizes of all scrollbars assuming that any scrollbars that could
-   * be visible due to overflowing content, are.
+   * be visible due to overflowing content, are. This can be called during reflow
+   * of the scrolled contents.
    */
   virtual nsMargin GetDesiredScrollbarSizes(nsBoxLayoutState* aState) = 0;
   /**
    * Return the sizes of all scrollbars assuming that any scrollbars that could
-   * be visible due to overflowing content, are.
+   * be visible due to overflowing content, are. This can be called during reflow
+   * of the scrolled contents.
    */
   virtual nsMargin GetDesiredScrollbarSizes(nsPresContext* aPresContext,
                                             nsIRenderingContext* aRC) = 0;

layout/xul/base/src/grid/nsGridRowLeafLayout.cpp

@@ -268,11 +268,15 @@ nsGridRowLeafLayout::ComputeChildSizes(nsIBox* aBox,
       nsIBox* scrollbox = nsGrid::GetScrollBox(parentBox);
       nsIScrollableFrame *scrollable = do_QueryFrame(scrollbox);
       if (scrollable) {
-        nsMargin scrollbarSizes = scrollable->GetActualScrollbarSizes();
+        // Don't call GetActualScrollbarSizes here because it's not safe
+        // to call that while we're reflowing the contents of the scrollframe,
+        // which we are here.
+        nsMargin scrollbarSizes = scrollable->GetDesiredScrollbarSizes(&aState);
+        PRUint32 visible = scrollable->GetScrollbarVisibility();
 
-        if (isHorizontal) {
+        if (isHorizontal && (visible & nsIScrollableFrame::VERTICAL)) {
           diff += scrollbarSizes.left + scrollbarSizes.right;
-        } else {
+        } else if (!isHorizontal && (visible & nsIScrollableFrame::HORIZONTAL)) {
           diff += scrollbarSizes.top + scrollbarSizes.bottom;
         }
       }