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..990e14fa8958c62e1e331334241492accc0aded7 100644
--- a/third_party/WebKit/Source/core/frame/History.cpp
+++ b/third_party/WebKit/Source/core/frame/History.cpp
@@ -139,9 +139,8 @@ 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())

[lfg, 2016/11/10 00:15:04]

We should probably merge these two functions, but let's do it in a separate
change.

     return;
 
   // We intentionally call reload() for the current frame if delta is zero.