Context dispose hint

patsje.patch

  diff --git a/src/node_contextify.cc b/src/node_contextify.cc
index f78f49f..718adb4 100644
--- a/src/node_contextify.cc
+++ b/src/node_contextify.cc
@@ -83,6 +83,15 @@ class ContextifyContext {
     context_.Dispose();
     proxy_global_.Dispose();
     sandbox_.Dispose();
+    // To prevent the DAG from this context from sticking around for too long,
+    // we give some strong hints to V8 that now is a good time to do a full GC.
+    // ContextDisposedNotification() makes IdleNotification() flush the current
+    // generation of ICs, which would otherwise prevent a full reclaim.
+    // Retiring the ICs means we set off a cascade of deoptimizations in the
+    // remaining contexts but there is nothing we can do about that.  If we
+    // don't take action, parts of the context may stick around indefinitely.
+    V8::ContextDisposedNotification();
+    V8::IdleNotification();
   }