PerformanceMonitor: do not maintain a vector of frames in the monitor, single ExecutionContext memb…

third_party/WebKit/Source/core/frame/LocalFrame.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Simon Hausmann <hausmann@kde.org>
  *                     2000 Stefan Schimanski <1Stein@gmx.de>
  *                     2001 George Staikos <staikos@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All
  * rights reserved.
  * Copyright (C) 2005 Alexey Proskuryakov <ap@nypop.com>
@@ skipping 407 matching lines @@
   ScriptForbiddenScope forbidScript;
   m_loader.clear();
   if (!client())
     return;
 
   client()->willBeDetached();
   // Notify ScriptController that the frame is closing, since its cleanup ends
   // up calling back to FrameLoaderClient via WindowProxy.
   script().clearForClose();
   setView(nullptr);
+  m_performanceMonitor->shutdown();

[caseq, 2016/12/01 02:04:03]

This does not look good already.

 
   m_host->eventHandlerRegistry().didRemoveAllEventHandlers(*localDOMWindow());
 
   localDOMWindow()->frameDestroyed();
 
   // TODO: Page should take care of updating focus/scrolling instead of Frame.
   // TODO: It's unclear as to why this is called more than once, but it is,
   // so page() could be null.
   if (page() && page()->focusController().focusedFrame() == this)
     page()->focusController().setFocusedFrame(nullptr);
@@ skipping 488 matching lines @@
   if (m_frame && m_frame->client() && m_frame->client()->frameBlameContext())
     m_frame->client()->frameBlameContext()->Enter();
 }
 
 ScopedFrameBlamer::~ScopedFrameBlamer() {
   if (m_frame && m_frame->client() && m_frame->client()->frameBlameContext())
     m_frame->client()->frameBlameContext()->Leave();
 }
 
 }  // namespace blink