[DevTools] filter any messages from previous session in DevToolsAgentHostImpl

chrome/browser/devtools/devtools_window.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/devtools/devtools_window.h"
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/json/json_reader.h"
@@ skipping 502 matching lines @@
     window->CloseWindow();
 }
 
 // static
 void DevToolsWindow::InspectElement(
     content::RenderFrameHost* inspected_frame_host,
     int x,
     int y) {
   scoped_refptr<DevToolsAgentHost> agent(
       DevToolsAgentHost::GetOrCreateFor(inspected_frame_host));
-  agent->InspectElement(x, y);
   bool should_measure_time = FindDevToolsWindow(agent.get()) == NULL;
   base::TimeTicks start_time = base::TimeTicks::Now();
   // TODO(loislo): we should initiate DevTools window opening from within
   // renderer. Otherwise, we still can hit a race condition here.
   if (agent->GetType() == content::DevToolsAgentHost::TYPE_WEB_CONTENTS) {
     OpenDevToolsWindow(agent->GetWebContents());
   } else {
     OpenDevToolsWindow(Profile::FromBrowserContext(agent->GetBrowserContext()),
                        agent);
   }
 
+  agent->InspectElement(x, y);

[pfeldman, 2015/11/13 17:38:12]

Lets land this separately.

+
   DevToolsWindow* window = FindDevToolsWindow(agent.get());
   if (should_measure_time && window)
     window->inspect_element_start_time_ = start_time;
 }
 
 // static
 content::DevToolsExternalAgentProxyDelegate*
 DevToolsWindow::CreateWebSocketAPIChannel(const std::string& path) {
   if (path.find("/devtools/frontend_api") != 0)
     return nullptr;
@@ skipping 728 matching lines @@
 bool DevToolsWindow::ReloadInspectedWebContents(bool ignore_cache) {
   // Only route reload via front-end if the agent is attached.
   WebContents* wc = GetInspectedWebContents();
   if (!wc || wc->GetCrashedStatus() != base::TERMINATION_STATUS_STILL_RUNNING)
     return false;
   base::FundamentalValue ignore_cache_value(ignore_cache);
   bindings_->CallClientFunction("DevToolsAPI.reloadInspectedPage",
                                 &ignore_cache_value, nullptr, nullptr);
   return true;
 }