From c91003698de0b2ce5371b43dca1e3524a0e55b44 Mon Sep 17 00:00:00 2001
From: Matt Woodrow <mwoodrow@mozilla.com>
Date: Wed, 17 Oct 2012 10:30:37 +1300
Subject: [PATCH] Bug 750417 - Remove Redraw calls from nsSprocketLayout. r=roc

---
 layout/xul/base/src/nsSprocketLayout.cpp | 20 +++-----------------
 layout/xul/base/src/nsSprocketLayout.h   |  3 +--
 2 files changed, 4 insertions(+), 19 deletions(-)

diff --git a/layout/xul/base/src/nsSprocketLayout.cpp b/layout/xul/base/src/nsSprocketLayout.cpp
index 65b64a5357d3..66deea55d776 100644
--- a/layout/xul/base/src/nsSprocketLayout.cpp
+++ b/layout/xul/base/src/nsSprocketLayout.cpp
@@ -251,7 +251,6 @@ nsSprocketLayout::Layout(nsIFrame* aBox, nsBoxLayoutState& aState)
   }
 
   // With the sizes computed, now it's time to lay out our children.
-  bool needsRedraw = false;
   bool finished;
   nscoord passes = 0;
 
@@ -472,15 +471,8 @@ nsSprocketLayout::Layout(nsIFrame* aBox, nsBoxLayoutState& aState)
            
         // set it again
         child->SetBounds(aState, childRect);
-
-        // Since the child changed size, we know a redraw is probably going to be required.
-        needsRedraw = true;
       }
 
-      // if something moved then we might need to redraw
-      if (oldRect.x != childRect.x || oldRect.y != childRect.y)
-          needsRedraw = true;
-
       // If we already determined that layout was required or if our size has changed, then
       // we make sure to call layout on the child, since its children may need to be shifted
       // around as a result of the size change.
@@ -632,13 +624,9 @@ nsSprocketLayout::Layout(nsIFrame* aBox, nsBoxLayoutState& aState)
 
   // Perform out-of-axis alignment for non-stretch alignments
   if (!(frameState & NS_STATE_AUTO_STRETCH)) {
-    AlignChildren(aBox, aState, &needsRedraw);
+    AlignChildren(aBox, aState);
   }
-
-  // Now do our redraw.
-  if (needsRedraw)
-    aBox->Redraw(aState);
-
+  
   // That's it!  If you made it this far without having a nervous breakdown, 
   // congratulations!  Go get yourself a beer.
   return NS_OK;
@@ -919,8 +907,7 @@ nsSprocketLayout::ComputeChildsNextPosition(nsIFrame* aBox,
 
 void
 nsSprocketLayout::AlignChildren(nsIFrame* aBox,
-                                nsBoxLayoutState& aState,
-                                bool* aNeedsRedraw)
+                                nsBoxLayoutState& aState)
 {
   nsFrameState frameState = 0;
   GetFrameState(aBox, frameState);
@@ -1005,7 +992,6 @@ nsSprocketLayout::AlignChildren(nsIFrame* aBox,
     }
 
     if (childRect.TopLeft() != child->GetPosition()) {
-      *aNeedsRedraw = true;
       child->SetBounds(aState, childRect);
     }
 
diff --git a/layout/xul/base/src/nsSprocketLayout.h b/layout/xul/base/src/nsSprocketLayout.h
index 21addaa12610..7e7725981f21 100644
--- a/layout/xul/base/src/nsSprocketLayout.h
+++ b/layout/xul/base/src/nsSprocketLayout.h
@@ -110,8 +110,7 @@ protected:
                     bool& aFinished);
 
   void AlignChildren(nsIFrame* aBox,
-                     nsBoxLayoutState& aState,
-                     bool* aNeedsRedraw);
+                     nsBoxLayoutState& aState);
 
   virtual void ComputeChildSizes(nsIFrame* aBox, 
                          nsBoxLayoutState& aState,