made using nsViewManager2 depend on the preference "nglayout.view.useViewManager2". r=pavlov, kmcclusk

view/src/nsViewFactory.cpp

@@ -110,8 +110,9 @@ nsresult nsViewFactory::LockFactory(PRBool aLock)
 }
 
 //Uncomment the following line to go back to the "new" compositor.
-#define USE_NEW_COMPOSITOR 1
+//#define USE_NEW_COMPOSITOR 1
 
+#if 0
 #if USE_NEW_COMPOSITOR
 #include "nsViewManager.h"
 NS_GENERIC_FACTORY_CONSTRUCTOR(nsViewManager)
@@ -119,6 +120,31 @@ NS_GENERIC_FACTORY_CONSTRUCTOR(nsViewManager)
 #include "nsViewManager2.h"
 NS_GENERIC_FACTORY_CONSTRUCTOR(nsViewManager2)
 #define nsViewManagerConstructor nsViewManager2Constructor
+#endif
+#else
+
+#include "nsViewManager.h"
+#include "nsViewManager2.h"
+#include "nsIPref.h"
+
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsViewManager)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsViewManager2)
+
+static NS_IMETHODIMP ViewManagerConstructor(nsISupports *aOuter, REFNSIID aIID, void **aResult)
+{
+	PRBool useViewManager2 = PR_FALSE;
+	nsresult rv;
+	NS_WITH_SERVICE(nsIPref, prefs, NS_PREF_PROGID, &rv);
+	if (NS_SUCCEEDED(rv))
+		prefs->GetBoolPref("nglayout.view.useViewManager2", &useViewManager2);
+	if (useViewManager2)
+		return nsViewManager2Constructor(aOuter, aIID, aResult);
+	else
+		return nsViewManagerConstructor(aOuter, aIID, aResult);
+}
+
+#define nsViewManagerConstructor ViewManagerConstructor
+
 #endif
 
 //////////////////////////////////////////////////////////////////////