Attempt 2 at: Fixes crash that occured because NativeViewHostAura::Detach was not

content/browser/renderer_host/render_widget_host_view_aura.cc

Index: content/browser/renderer_host/render_widget_host_view_aura.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.cc b/content/browser/renderer_host/render_widget_host_view_aura.cc
index d70875ca83e33c1cc793d98d160ac69202c34529..7130feccda896557be15de267772c07d2f41abf8 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.cc
+++ b/content/browser/renderer_host/render_widget_host_view_aura.cc
@@ -338,7 +338,11 @@ void RenderWidgetHostViewAura::MovePluginWindows(
 }
 
 void RenderWidgetHostViewAura::Focus() {
-  window_->Focus();
+  // Make sure we have a FocusManager before attempting to Focus(). In some
+  // situations we may not yet be in a valid Window hierarchy (such as reloading
+  // after out of memory discared the tab).
+  if (window_->GetFocusManager())
+    window_->Focus();
 }
 
 void RenderWidgetHostViewAura::Blur() {