Bug 1510569 - Add nsIWebProgressListener2 to BrowserChild's interface map r=Ehsan

The members of nsIWebProgressListener2 were added to BrowserChild (then
TabChild) in commit 1028814583232487b52b9c20d47e3b38dc1c288a, but the interface
was never added to the interface map.

Differential Revision: https://phabricator.services.mozilla.com/D35134

--HG--
extra : moz-landing-system : lando

dom/ipc/BrowserChild.cpp

@@ -671,6 +671,7 @@ NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(BrowserChild)
   NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
   NS_INTERFACE_MAP_ENTRY(nsITooltipListener)
   NS_INTERFACE_MAP_ENTRY(nsIWebProgressListener)
+  NS_INTERFACE_MAP_ENTRY(nsIWebProgressListener2)
   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIBrowserChild)
 NS_INTERFACE_MAP_END