Allow navigations to frames that aren't being unloaded in the unload handler.

third_party/WebKit/Source/core/frame/History.cpp

Index: third_party/WebKit/Source/core/frame/History.cpp
diff --git a/third_party/WebKit/Source/core/frame/History.cpp b/third_party/WebKit/Source/core/frame/History.cpp
index ff278e4d8c74cc3ff2685cc5e9a663d3f5dd44c4..8117a1258a68a9cd6ab7adac3d9a55e120f4df59 100644
--- a/third_party/WebKit/Source/core/frame/History.cpp
+++ b/third_party/WebKit/Source/core/frame/History.cpp
@@ -139,10 +139,11 @@ void History::go(ExecutionContext* context, int delta) {
     return;
 
   if (!activeDocument->frame() ||
-      !activeDocument->frame()->canNavigate(*frame()))
-    return;
-  if (!NavigationDisablerForUnload::isNavigationAllowed())
+      !activeDocument->frame()->canNavigate(*frame()) ||
+      !activeDocument->frame()->isNavigationAllowed() ||
+      !NavigationDisablerForBeforeUnload::isNavigationAllowed()) {
     return;
+  }
 
   // We intentionally call reload() for the current frame if delta is zero.
   // Otherwise, navigation happens on the root frame.