diff --git a/dom/base/nsContentUtils.h b/dom/base/nsContentUtils.h
index 266b30767d9e..480696309897 100644
--- a/dom/base/nsContentUtils.h
+++ b/dom/base/nsContentUtils.h
@@ -106,7 +106,6 @@ class nsIWindowProvider;
 
 struct JSPropertyDescriptor;
 struct JSRuntime;
-struct nsIntMargin;
 
 template<class E> class nsCOMArray;
 template<class K, class V> class nsDataHashtable;
diff --git a/gfx/src/nsITheme.h b/gfx/src/nsITheme.h
index 4b458faf1b8f..d0d7838b6a46 100644
--- a/gfx/src/nsITheme.h
+++ b/gfx/src/nsITheme.h
@@ -15,7 +15,6 @@
 #include "Units.h"
 
 struct nsRect;
-struct nsIntMargin;
 class nsPresContext;
 class nsRenderingContext;
 class nsDeviceContext;
diff --git a/gfx/src/nsMargin.h b/gfx/src/nsMargin.h
index cf824cc9e09b..d9b0b8bd9a5c 100644
--- a/gfx/src/nsMargin.h
+++ b/gfx/src/nsMargin.h
@@ -9,6 +9,7 @@
 #include "nsCoord.h"
 #include "nsPoint.h"
 #include "mozilla/gfx/BaseMargin.h"
+#include "mozilla/gfx/Rect.h"
 
 struct nsMargin : public mozilla::gfx::BaseMargin<nscoord, nsMargin> {
   typedef mozilla::gfx::BaseMargin<nscoord, nsMargin> Super;
@@ -20,14 +21,6 @@ struct nsMargin : public mozilla::gfx::BaseMargin<nscoord, nsMargin> {
     : Super(aTop, aRight, aBottom, aLeft) {}
 };
 
-struct nsIntMargin : public mozilla::gfx::BaseMargin<int32_t, nsIntMargin> {
-  typedef mozilla::gfx::BaseMargin<int32_t, nsIntMargin> Super;
-
-  // Constructors
-  nsIntMargin() : Super() {}
-  nsIntMargin(const nsIntMargin& aMargin) : Super(aMargin) {}
-  nsIntMargin(int32_t aTop, int32_t aRight, int32_t aBottom, int32_t aLeft)
-    : Super(aTop, aRight, aBottom, aLeft) {}
-};
+typedef mozilla::gfx::IntMargin nsIntMargin;
 
 #endif /* NSMARGIN_H */
diff --git a/gfx/src/nsRect.h b/gfx/src/nsRect.h
index 9b986e8bf5a2..2907628cd487 100644
--- a/gfx/src/nsRect.h
+++ b/gfx/src/nsRect.h
@@ -15,12 +15,10 @@
 #include "nsCoord.h"                    // for nscoord, etc
 #include "nsISupportsImpl.h"            // for MOZ_COUNT_CTOR, etc
 #include "nsPoint.h"                    // for nsIntPoint, nsPoint
+#include "nsMargin.h"                   // for nsIntMargin, nsMargin
 #include "nsSize.h"                     // for IntSize, nsSize
 #include "nscore.h"                     // for NS_BUILD_REFCNT_LOGGING
 
-struct nsMargin;
-struct nsIntMargin;
-
 typedef mozilla::gfx::IntRect nsIntRect;
 
 struct nsRect :