diff --git a/gfx/gl/GLUploadHelpers.cpp b/gfx/gl/GLUploadHelpers.cpp
index 0a650419844..b92c47a61d9 100644
--- a/gfx/gl/GLUploadHelpers.cpp
+++ b/gfx/gl/GLUploadHelpers.cpp
@@ -501,30 +501,29 @@ UploadImageDataToTexture(GLContext* gl,
             NS_ASSERTION(false, "Unhandled image surface format!");
     }
 
-    nsIntRegionRectIterator iter(paintRegion);
-    const IntRect *iterRect;
 
     // Top left point of the region's bounding rectangle.
     IntPoint topLeft = paintRegion.GetBounds().TopLeft();
 
-    while ((iterRect = iter.Next())) {
+    for (auto iter = paintRegion.RectIter(); !iter.Done(); iter.Next()) {
+        const IntRect& rect = iter.Get();
         // The inital data pointer is at the top left point of the region's
         // bounding rectangle. We need to find the offset of this rect
         // within the region and adjust the data pointer accordingly.
         unsigned char *rectData =
-            aData + DataOffset(iterRect->TopLeft() - topLeft, aStride, aFormat);
+            aData + DataOffset(rect.TopLeft() - topLeft, aStride, aFormat);
 
-        NS_ASSERTION(textureInited || (iterRect->x == 0 && iterRect->y == 0),
+        NS_ASSERTION(textureInited || (rect.x == 0 && rect.y == 0),
                      "Must be uploading to the origin when we don't have an existing texture");
 
         if (textureInited && CanUploadSubTextures(gl)) {
             TexSubImage2DHelper(gl,
                                 aTextureTarget,
                                 0,
-                                iterRect->x,
-                                iterRect->y,
-                                iterRect->width,
-                                iterRect->height,
+                                rect.x,
+                                rect.y,
+                                rect.width,
+                                rect.height,
                                 aStride,
                                 pixelSize,
                                 format,
@@ -535,8 +534,8 @@ UploadImageDataToTexture(GLContext* gl,
                              aTextureTarget,
                              0,
                              internalFormat,
-                             iterRect->width,
-                             iterRect->height,
+                             rect.width,
+                             rect.height,
                              aStride,
                              pixelSize,
                              0,
diff --git a/gfx/ipc/GfxMessageUtils.h b/gfx/ipc/GfxMessageUtils.h
index e4bc6162fc4..f19948145f2 100644
--- a/gfx/ipc/GfxMessageUtils.h
+++ b/gfx/ipc/GfxMessageUtils.h
@@ -367,10 +367,10 @@ struct RegionParamTraits
 
   static void Write(Message* msg, const paramType& param)
   {
-    Iter it(param);
-    while (const Rect* r = it.Next()) {
-      MOZ_RELEASE_ASSERT(!r->IsEmpty());
-      WriteParam(msg, *r);
+    for (auto iter = param.RectIter(); !iter.Done(); iter.Next()) {
+      const Rect& r = iter.Get();
+      MOZ_RELEASE_ASSERT(!r.IsEmpty());
+      WriteParam(msg, r);
     }
     // empty rects are sentinel values because nsRegions will never
     // contain them
@@ -393,7 +393,7 @@ template<class Units>
 struct ParamTraits<mozilla::gfx::IntRegionTyped<Units>>
   : RegionParamTraits<mozilla::gfx::IntRegionTyped<Units>,
                       mozilla::gfx::IntRectTyped<Units>,
-                      typename mozilla::gfx::IntRegionTyped<Units>::OldRectIterator>
+                      typename mozilla::gfx::IntRegionTyped<Units>::RectIterator>
 {};
 
 template<>
@@ -666,7 +666,7 @@ struct ParamTraits<nsRect>
 
 template<>
 struct ParamTraits<nsRegion>
-  : RegionParamTraits<nsRegion, nsRect, nsRegionRectIterator>
+  : RegionParamTraits<nsRegion, nsRect, nsRegion::RectIterator>
 {};
 
 template <>
diff --git a/gfx/layers/Compositor.cpp b/gfx/layers/Compositor.cpp
index 457cb0d6873..43c3ebf6651 100644
--- a/gfx/layers/Compositor.cpp
+++ b/gfx/layers/Compositor.cpp
@@ -58,12 +58,9 @@ Compositor::DrawDiagnostics(DiagnosticFlags aFlags,
   }
 
   if (aVisibleRegion.GetNumRects() > 1) {
-    nsIntRegionRectIterator screenIter(aVisibleRegion);
-
-    while (const gfx::IntRect* rect = screenIter.Next())
-    {
+    for (auto iter = aVisibleRegion.RectIter(); !iter.Done(); iter.Next()) {
       DrawDiagnostics(aFlags | DiagnosticFlags::REGION_RECT,
-                      IntRectToRect(*rect), aClipRect, aTransform,
+                      IntRectToRect(iter.Get()), aClipRect, aTransform,
                       aFlashCounter);
     }
   }
diff --git a/gfx/layers/LayerTreeInvalidation.cpp b/gfx/layers/LayerTreeInvalidation.cpp
index 146ff820b2f..941d7c7ad6b 100644
--- a/gfx/layers/LayerTreeInvalidation.cpp
+++ b/gfx/layers/LayerTreeInvalidation.cpp
@@ -83,10 +83,8 @@ TransformRect(const IntRect& aRect, const Matrix4x4& aTransform)
 static void
 AddTransformedRegion(nsIntRegion& aDest, const nsIntRegion& aSource, const Matrix4x4& aTransform)
 {
-  nsIntRegionRectIterator iter(aSource);
-  const IntRect *r;
-  while ((r = iter.Next())) {
-    aDest.Or(aDest, TransformRect(*r, aTransform));
+  for (auto iter = aSource.RectIter(); !iter.Done(); iter.Next()) {
+    aDest.Or(aDest, TransformRect(iter.Get(), aTransform));
   }
   aDest.SimplifyOutward(20);
 }
diff --git a/gfx/layers/Layers.cpp b/gfx/layers/Layers.cpp
index 2d2075e8fff..079bb3a679e 100644
--- a/gfx/layers/Layers.cpp
+++ b/gfx/layers/Layers.cpp
@@ -1997,9 +1997,8 @@ DumpRect(layerscope::LayersPacket::Layer::Rect* aLayerRect,
 static void
 DumpRegion(layerscope::LayersPacket::Layer::Region* aLayerRegion, const nsIntRegion& aRegion)
 {
-  nsIntRegionRectIterator it(aRegion);
-  while (const IntRect* sr = it.Next()) {
-    DumpRect(aLayerRegion->add_r(), *sr);
+  for (auto iter = aRegion.RectIter(); !iter.Done(); iter.Next()) {
+    DumpRect(aLayerRegion->add_r(), iter.Get());
   }
 }