Remove CHECK after diagnosing crash.

BUG=730398
R=pdr@chromium.org

Change-Id: I61868a97e920d0131d672952b7d570181da11537
Reviewed-on: https://chromium-review.googlesource.com/565806Reviewed-by: Philip Rogers <pdr@chromium.org>
Commit-Queue: Stefan Zager <szager@chromium.org>
Cr-Commit-Position: refs/heads/master@{#485451}

third_party/WebKit/Source/core/dom/Document.cpp

@@ -1800,9 +1800,6 @@ void Document::ScheduleLayoutTreeUpdate() {
   DCHECK(ShouldScheduleLayoutTreeUpdate());
   DCHECK(NeedsLayoutTreeUpdate());
 
-  // TODO(szager): Remove this CHECK after checking crash reports.
-  CHECK(lifecycle_.GetState() != DocumentLifecycle::kInPerformLayout);
-
   if (!View()->CanThrottleRendering())
     GetPage()->Animator().ScheduleVisualUpdate(GetFrame());
   lifecycle_.EnsureStateAtMost(DocumentLifecycle::kVisualUpdatePending);