Fix RenderWidgetHostViewGuest leak.

content/browser/renderer_host/render_widget_host_view_mac.mm

Index: content/browser/renderer_host/render_widget_host_view_mac.mm
diff --git a/content/browser/renderer_host/render_widget_host_view_mac.mm b/content/browser/renderer_host/render_widget_host_view_mac.mm
index 9785c559e6bc2c4469af8ac1b63045aa6e3eb82e..e6e3a2100436d1902c30b8160ec16cf5428d8358 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.mm
+++ b/content/browser/renderer_host/render_widget_host_view_mac.mm
@@ -570,8 +570,10 @@ RenderWidgetHostViewMac::~RenderWidgetHostViewMac() {
   // We are owned by RenderWidgetHostViewCocoa, so if we go away before the
   // RenderWidgetHost does we need to tell it not to hold a stale pointer to
   // us.
-  if (render_widget_host_)
-    render_widget_host_->SetView(NULL);
+  if (render_widget_host_) {
+    if (render_widget_host_->GetView() == this)
+      render_widget_host_->SetView(NULL);

[lazyboy, 2014/10/10 01:22:58]

It might be consistent to call
render_widget_host_->ViewDestroyed() instead.

That function has additional
RWH::RejectMouseLockOrUnlockIfNecessary() call though, so
not sure about the side effect.

+  }
 }
 
 void RenderWidgetHostViewMac::SetDelegate(