Bug 1293596 (part 1) - Don't use NS_IMETHOD for nsIWidget::AttachViewToTopLevel. r=karlt.

view/nsView.cpp

@@ -691,9 +691,7 @@ nsresult nsView::AttachToTopLevelWidget(nsIWidget* aWidget)
 
   // Note, the previous device context will be released. Detaching
   // will not restore the old one.
-  nsresult rv = aWidget->AttachViewToTopLevel(!nsIWidget::UsePuppetWidgets());
-  if (NS_FAILED(rv))
-    return rv;
+  aWidget->AttachViewToTopLevel(!nsIWidget::UsePuppetWidgets());
 
   mWindow = aWidget;
 

widget/nsBaseWidget.cpp

@@ -475,7 +475,7 @@ nsBaseWidget::CreateChild(const LayoutDeviceIntRect& aRect,
 }
 
 // Attach a view to our widget which we'll send events to.
-NS_IMETHODIMP
+void
 nsBaseWidget::AttachViewToTopLevel(bool aUseAttachedEvents)
 {
   NS_ASSERTION((mWindowType == eWindowType_toplevel ||
@@ -485,8 +485,6 @@ nsBaseWidget::AttachViewToTopLevel(bool aUseAttachedEvents)
                "Can't attach to window of that type");
 
   mUseAttachedEvents = aUseAttachedEvents;
-
-  return NS_OK;
 }
 
 nsIWidgetListener* nsBaseWidget::GetAttachedWidgetListener()

widget/nsBaseWidget.h

@@ -262,7 +262,7 @@ public:
   CreateChild(const LayoutDeviceIntRect& aRect,
               nsWidgetInitData* aInitData = nullptr,
               bool aForceUseIWidgetParent = false) override;
-  NS_IMETHOD              AttachViewToTopLevel(bool aUseAttachedEvents) override;
+  virtual void            AttachViewToTopLevel(bool aUseAttachedEvents) override;
   virtual nsIWidgetListener* GetAttachedWidgetListener() override;
   virtual void               SetAttachedWidgetListener(nsIWidgetListener* aListener) override;
   virtual nsIWidgetListener* GetPreviouslyAttachedWidgetListener() override;

widget/nsIWidget.h

@@ -479,7 +479,7 @@ class nsIWidget : public nsISupports
      * aUseAttachedEvents if true, events are sent to the attached listener
      * instead of the normal listener.
      */
-    NS_IMETHOD AttachViewToTopLevel(bool aUseAttachedEvents) = 0;
+    virtual void AttachViewToTopLevel(bool aUseAttachedEvents) = 0;
 
     /**
      * Accessor functions to get and set the attached listener. Used by