Null check FocusedFrame in spatial navigation

third_party/WebKit/Source/core/page/FocusController.cpp

 /*
  * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nuanti Ltd.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 1324 matching lines @@
     Node* container = focus_candidate.enclosing_scrollable_box;
     ScrollInDirection(container, type);
     return true;
   }
 
   // We found a new focus node, navigate to it.
   Element* element = ToElement(focus_candidate.focusable_node);
   DCHECK(element);
 
   if (!element->IsTextControl() && !HasEditableStyle(*element->ToNode())) {
-    // To fulfill the expectation of spatial-navigation/snav-input.html
+    // To fulfill the expectation of spatial-navigation/snav-textarea.html
     // we clear selection when spatnav moves focus away from a text-field.
-    FocusedFrame()->Selection().Clear();
+    // TODO(hugoh@opera.com): crbug.com/734552 remove Selection.Clear()
+    if (FocusedFrame())
+      FocusedFrame()->Selection().Clear();
   }
   element->focus(FocusParams(SelectionBehaviorOnFocus::kReset, type, nullptr));
   return true;
 }
 
 bool FocusController::AdvanceFocusDirectionally(WebFocusType type) {
   // FIXME: Directional focus changes don't yet work with RemoteFrames.
   if (!FocusedOrMainFrame()->IsLocalFrame())
     return false;
   LocalFrame* cur_frame = ToLocalFrame(FocusedOrMainFrame());
@@ skipping 52 matching lines @@
     it->FocusedFrameChanged();
 }
 
 DEFINE_TRACE(FocusController) {
   visitor->Trace(page_);
   visitor->Trace(focused_frame_);
   visitor->Trace(focus_changed_observers_);
 }
 
 }  // namespace blink