Bug 352093. Part 2: Create nsIViewManager::GetRootWidget.

view/public/nsIViewManager.h

@@ -59,10 +59,9 @@ enum nsRectVisibility {
   nsRectVisibility_kZeroAreaRect
 }; 
 
-// 98f676da-eb1a-467d-9c0e-0d64c2c88d85
 #define NS_IVIEWMANAGER_IID   \
-  { 0x98f676da, 0xeb1a, 0x467d, \
-    { 0x9c, 0x0e, 0x0d, 0x64, 0xc2, 0xc8, 0x8d, 0x85 } }
+  { 0x50c0a18c, 0x3e39, 0x4606, \
+    { 0x85, 0x77, 0xe7, 0x3a, 0xcc, 0xb4, 0x66, 0xc9 } }
 
 class nsIViewManager : public nsISupports
 {
@@ -424,6 +423,12 @@ public:
    */
   NS_IMETHOD GetWidget(nsIWidget **aWidget) = 0;
 
+  /**
+   * Retrieve the widget at the root of the nearest enclosing
+   * view manager whose root view has a widget.
+   */
+  NS_IMETHOD GetRootWidget(nsIWidget **aWidget) = 0;
+
   /**
    * Force update of view manager widget
    * Callers should use UpdateView(view, NS_VMREFRESH_IMMEDIATE) in most cases instead

view/src/nsViewManager.cpp

@@ -1874,6 +1874,23 @@ NS_IMETHODIMP nsViewManager::GetWidget(nsIWidget **aWidget)
   return NS_OK;
 }
 
+NS_IMETHODIMP nsViewManager::GetRootWidget(nsIWidget **aWidget)
+{
+  if (!mRootView) {
+    *aWidget = nsnull;
+    return NS_OK;
+  }
+  if (mRootView->HasWidget()) {
+    *aWidget = mRootView->GetWidget();
+    NS_ADDREF(*aWidget);
+    return NS_OK;
+  }
+  if (mRootView->GetParent())
+    return mRootView->GetParent()->GetViewManager()->GetRootWidget(aWidget);
+  *aWidget = nsnull;
+  return NS_OK;
+}
+
 NS_IMETHODIMP nsViewManager::ForceUpdate()
 {
   if (!IsRootVM()) {

view/src/nsViewManager.h

@@ -173,6 +173,7 @@ public:
 
   NS_IMETHOD GetWidget(nsIWidget **aWidget);
   nsIWidget* GetWidget() { return mRootView ? mRootView->GetWidget() : nsnull; }
+  NS_IMETHOD GetRootWidget(nsIWidget **aWidget);
   NS_IMETHOD ForceUpdate();
  
   NS_IMETHOD IsPainting(PRBool& aIsPainting);