Remove bogus assertion from idle notification.

Callbacks that run after garbage collection might fire a context dispose
notification and hence increse the counter before we actually reach this
position.

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/11280214

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13080 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/heap.cc

@@ -5330,10 +5330,6 @@ bool Heap::IdleNotification(int hint) {
       AdvanceIdleIncrementalMarking(step_size);
       contexts_disposed_ = 0;
     }
-    // Make sure that we have no pending context disposals.
-    // Take into account that we might have decided to delay full collection
-    // because incremental marking is in progress.
-    ASSERT((contexts_disposed_ == 0) || !incremental_marking()->IsStopped());
     // After context disposal there is likely a lot of garbage remaining, reset
     // the idle notification counters in order to trigger more incremental GCs
     // on subsequent idle notifications.