Bug 1287624, part 2 - Replace swap with forget in a few places. r=froydnj

The return argument was initialized to null in all of these, so it
should not change the behavior.

netwerk/base/nsInputStreamPump.cpp

@@ -66,8 +66,7 @@ nsInputStreamPump::Create(nsInputStreamPump  **result,
         rv = pump->Init(stream, streamPos, streamLen,
                         segsize, segcount, closeWhenDone);
         if (NS_SUCCEEDED(rv)) {
-            *result = nullptr;
-            pump.swap(*result);
+            pump.forget(result);
         }
     }
     return rv;

toolkit/components/places/nsNavHistoryQuery.cpp

@@ -1506,8 +1506,6 @@ nsNavHistoryQueryOptions::Clone(nsNavHistoryQueryOptions **aResult)
 {
   *aResult = nullptr;
   nsNavHistoryQueryOptions *result = new nsNavHistoryQueryOptions();
-  if (! result)
-    return NS_ERROR_OUT_OF_MEMORY;
 
   RefPtr<nsNavHistoryQueryOptions> resultHolder(result);
   result->mSort = mSort;
@@ -1520,7 +1518,7 @@ nsNavHistoryQueryOptions::Clone(nsNavHistoryQueryOptions **aResult)
   result->mParentAnnotationToExclude = mParentAnnotationToExclude;
   result->mAsyncEnabled = mAsyncEnabled;
 
-  resultHolder.swap(*aResult);
+  resultHolder.forget(aResult);
   return NS_OK;
 }
 

xpfe/appshell/nsAppShellService.cpp

@@ -778,7 +778,7 @@ nsAppShellService::JustCreateTopWindow(nsIXULWindow *aParent,
     thisContext->SetRemoteTabs(isUsingRemoteTabs);
   }
 
-  window.swap(*aResult); // transfer reference
+  window.forget(aResult);
   if (parent)
     parent->AddChildWindow(*aResult);