diff --git a/mozilla/xpcom/base/nsAutoPtr.h b/mozilla/xpcom/base/nsAutoPtr.h
index 5b3757561d1..d078254074a 100644
--- a/mozilla/xpcom/base/nsAutoPtr.h
+++ b/mozilla/xpcom/base/nsAutoPtr.h
@@ -1042,6 +1042,17 @@ class nsRefPtr
           return temp;
         }
 
+      void
+      forget( T** rhs )
+          // Set the target of rhs to the value of mRawPtr and null out mRawPtr.
+          // Useful to avoid unnecessary AddRef/Release pairs with "out"
+          // parameters.
+        {
+          NS_ASSERTION(rhs, "Null pointer passed to forget!");
+          *rhs = 0;
+          swap(*rhs);
+        }
+
       T*
       get() const
           /*
diff --git a/mozilla/xpcom/glue/nsCOMPtr.h b/mozilla/xpcom/glue/nsCOMPtr.h
index c4799e22d5f..22bd959b124 100644
--- a/mozilla/xpcom/glue/nsCOMPtr.h
+++ b/mozilla/xpcom/glue/nsCOMPtr.h
@@ -829,6 +829,17 @@ class nsCOMPtr
           return temp;
         }
 
+      void
+      forget( T** rhs )
+          // Set the target of rhs to the value of mRawPtr and null out mRawPtr.
+          // Useful to avoid unnecessary AddRef/Release pairs with "out"
+          // parameters.
+        {
+          NS_ASSERTION(rhs, "Null pointer passed to forget!");
+          *rhs = 0;
+          swap(*rhs);
+        }
+
       T*
       get() const
           /*
@@ -1139,6 +1150,16 @@ class nsCOMPtr<nsISupports>
           mRawPtr = temp;
         }
 
+      void
+      forget( nsISupports** rhs )
+          // Set the target of rhs to the value of mRawPtr and null out mRawPtr.
+          // Useful to avoid unnecessary AddRef/Release pairs with "out"
+          // parameters.
+        {
+          NS_ASSERTION(rhs, "Null pointer passed to forget!");
+          *rhs = 0;
+          swap(*rhs);
+        }
 
         // Other pointer operators