diff --git a/extensions/xmlterm/base/mozXMLTermStream.cpp b/extensions/xmlterm/base/mozXMLTermStream.cpp
index 543a0506e2e7..c9593e222f84 100644
--- a/extensions/xmlterm/base/mozXMLTermStream.cpp
+++ b/extensions/xmlterm/base/mozXMLTermStream.cpp
@@ -56,7 +56,6 @@
 
 #include "nsIViewManager.h"
 #include "nsIScrollableView.h"
-#include "nsIDeviceContext.h"
 #include "nsIFrame.h"
 
 #include "nsICategoryManager.h"
@@ -380,20 +379,12 @@ NS_IMETHODIMP mozXMLTermStream::SizeToContentHeight(PRInt32 maxHeight)
   if (NS_FAILED(result) || !scrollableView)
     return NS_ERROR_FAILURE;
 
-  // Get device context
-  nsCOMPtr<nsIDeviceContext> deviceContext;
-  result = mozXMLTermUtils::GetPresContextDeviceContext(presContext,
-                                              getter_AddRefs(deviceContext));
-  if (NS_FAILED(result) || !deviceContext)
-    return NS_ERROR_FAILURE;
-
   // Determine twips to pixels conversion factor
   float pixelScale;
   pixelScale = presContext->TwipsToPixels();
 
-  // Get scrollbar dimensions in pixels
-  float sbWidth, sbHeight;
-  deviceContext->GetScrollBarDimensions(sbWidth, sbHeight);
+  // Get scrollbar dimensions in pixels.  Ideally we'd measure the actual scrollbars here.
+  float sbWidth = 15.0, sbHeight = 15.0;
   PRInt32 scrollBarWidth = PRInt32(sbWidth*pixelScale);
   PRInt32 scrollBarHeight = PRInt32(sbHeight*pixelScale);
 
diff --git a/layout/forms/nsComboboxControlFrame.cpp b/layout/forms/nsComboboxControlFrame.cpp
index eed89790c1db..438b964ef7ef 100644
--- a/layout/forms/nsComboboxControlFrame.cpp
+++ b/layout/forms/nsComboboxControlFrame.cpp
@@ -89,6 +89,7 @@
 #include "nsContentCreatorFunctions.h"
 #include "nsLayoutUtils.h"
 #include "nsDisplayList.h"
+#include "nsBoxLayoutState.h"
 
 NS_IMETHODIMP
 nsComboboxControlFrame::RedisplayTextEvent::Run()
@@ -659,15 +660,13 @@ nsComboboxControlFrame::Reflow(nsPresContext*          aPresContext,
   // First reflow our dropdown so that we know how tall we should be.
   ReflowDropdown(aPresContext, aReflowState);
   
-  // Get the default size of the scrollbar.
-  // That will be the default width of the dropdown button.
-  // The height will be the height of the text
-  // Can we cache this in a meaningful way?
-  float w, h;
-  // Get the width in Device pixels times p2t
-  aPresContext->DeviceContext()->GetScrollBarDimensions(w, h);
-
-  nscoord buttonWidth = NSToCoordRound(w);
+  // Get the width of the vertical scrollbar.  That will be the width of the
+  // dropdown button.
+  nsIScrollableFrame* scrollable;
+  CallQueryInterface(mListControlFrame, &scrollable);
+  NS_ASSERTION(scrollable, "List must be a scrollable frame");
+  nsBoxLayoutState bls(GetPresContext(), aReflowState.rendContext);
+  nscoord buttonWidth = scrollable->GetDesiredScrollbarSizes(&bls).LeftRight();
 
   if (buttonWidth > aReflowState.mComputedWidth) {
     buttonWidth = 0;
diff --git a/layout/forms/nsTextControlFrame.cpp b/layout/forms/nsTextControlFrame.cpp
index b6d47d7b4fe9..7c5ab7131d24 100644
--- a/layout/forms/nsTextControlFrame.cpp
+++ b/layout/forms/nsTextControlFrame.cpp
@@ -1360,24 +1360,18 @@ nsTextControlFrame::CalcIntrinsicSize(nsIRenderingContext* aRenderingContext,
 
   // Add in the size of the scrollbars for textarea
   if (IsTextArea()) {
-    float p2t;
-    p2t = presContext->PixelsToTwips();
+    nsIFrame* first = GetFirstChild(nsnull);
 
-    nsIDeviceContext *dx = presContext->DeviceContext();
+    nsIScrollableFrame *scrollableFrame;
+    CallQueryInterface(first, &scrollableFrame);
+    NS_ASSERTION(scrollableFrame, "Child must be scrollable");
 
-    float   scale;
-    dx->GetCanonicalPixelScale(scale);
+    nsBoxLayoutState bls(GetPresContext(), aRenderingContext);
+    nsMargin scrollbarSizes = scrollableFrame->GetDesiredScrollbarSizes(&bls);
 
-    float sbWidth;
-    float sbHeight;
-    dx->GetScrollBarDimensions(sbWidth, sbHeight);
-
-    nscoord scrollbarWidth  = PRInt32(sbWidth * scale);
-    nscoord scrollbarHeight = PRInt32(sbHeight * scale);
-
-    aIntrinsicSize.height += scrollbarHeight;
-
-    aIntrinsicSize.width  += scrollbarWidth;
+    aIntrinsicSize.width  += scrollbarSizes.LeftRight();
+    
+    aIntrinsicSize.height += scrollbarSizes.TopBottom();;
   }
 
   return NS_OK;