--- a/layout/base/PresShell.h
+++ b/layout/base/PresShell.h
@@ -19,16 +19,17 @@
 /* a presentation of a document, part 2 */
 
 #ifndef mozilla_PresShell_h
 #define mozilla_PresShell_h
 
 #include "MobileViewportManager.h"
 #include "mozilla/Attributes.h"
 #include "mozilla/EventForwards.h"
+#include "mozilla/layers/FocusTarget.h"
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/StyleSetHandle.h"
 #include "mozilla/UniquePtr.h"
 #include "nsAutoPtr.h"
 #include "nsContentUtils.h" // For AddScriptBlocker().
 #include "nsCRT.h"
 #include "nsIObserver.h"
 #include "nsIPresShell.h"
@@ -80,16 +81,19 @@ typedef nsClassHashtable<nsUint64HashKey
 #endif
 
 class PresShell final : public nsIPresShell,
                         public nsStubDocumentObserver,
                         public nsISelectionController,
                         public nsIObserver,
                         public nsSupportsWeakReference
 {
+protected:
+  typedef mozilla::layers::FocusTarget FocusTarget;
+
 public:
   PresShell();
 
   // nsISupports
   NS_DECL_ISUPPORTS
 
   static bool AccessibleCaretEnabled(nsIDocShell* aDocShell);
 

--- a/layout/base/nsIPresShell.h
+++ b/layout/base/nsIPresShell.h
@@ -18,17 +18,16 @@
 /* a presentation of a document, part 2 */
 
 #ifndef nsIPresShell_h___
 #define nsIPresShell_h___
 
 #include "mozilla/ArenaObjectID.h"
 #include "mozilla/EventForwards.h"
 #include "mozilla/FlushType.h"
-#include "mozilla/layers/FocusTarget.h"
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/StaticPtr.h"
 #include "mozilla/StyleSetHandle.h"
 #include "mozilla/StyleSheet.h"
 #include "mozilla/WeakPtr.h"
 #include "gfxPoint.h"
 #include "nsTHashtable.h"
 #include "nsHashKeys.h"
@@ -176,17 +175,16 @@ enum nsRectVisibility {
  */
 
 class nsIPresShell : public nsISupports
 {
 public:
   NS_DECLARE_STATIC_IID_ACCESSOR(NS_IPRESSHELL_IID)
 
 protected:
-  typedef mozilla::layers::FocusTarget FocusTarget;
   typedef mozilla::layers::LayerManager LayerManager;
   typedef mozilla::gfx::SourceSurface SourceSurface;
 
   enum eRenderFlag {
     STATE_IGNORING_VIEWPORT_SCROLLING = 0x1,
     STATE_DRAWWINDOW_NOT_FLUSHING = 0x2
   };
   typedef uint8_t RenderFlags; // for storing the above flags