[DevTools] Only create DevToolsAgentHost for main frame and cross-process subframes.

content/browser/devtools/render_frame_devtools_agent_host.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 "content/browser/devtools/render_frame_devtools_agent_host.h"
 
 #include "base/basictypes.h"
 #include "base/lazy_instance.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/browser/child_process_security_policy_impl.h"
@@ skipping 51 matching lines @@
   if (g_instances == NULL)
     return NULL;
   for (Instances::iterator it = g_instances.Get().begin();
        it != g_instances.Get().end(); ++it) {
     if ((*it)->GetWebContents() == web_contents)
       return *it;
   }
   return NULL;
 }
 
+bool ShouldCreateDevToolsFor(RenderFrameHost* rfh) {
+  return rfh->IsCrossProcessSubframe() || !rfh->GetParent();
+}
+
 }  // namespace
 
 scoped_refptr<DevToolsAgentHost>
 DevToolsAgentHost::GetOrCreateFor(WebContents* web_contents) {
   RenderFrameDevToolsAgentHost* result = FindAgentHost(web_contents);
   if (!result)
     result = new RenderFrameDevToolsAgentHost(web_contents->GetMainFrame());
   return result;
 }
 
 // static
 scoped_refptr<DevToolsAgentHost> RenderFrameDevToolsAgentHost::GetOrCreateFor(
     RenderFrameHost* host) {
   RenderFrameDevToolsAgentHost* result = FindAgentHost(host);
   if (!result)
     result = new RenderFrameDevToolsAgentHost(host);
   return result;
 }
 
 // static
 void RenderFrameDevToolsAgentHost::AppendAgentHostForFrameIfApplicable(
     DevToolsAgentHost::List* result,
     RenderFrameHost* host) {
   RenderFrameHostImpl* rfh = static_cast<RenderFrameHostImpl*>(host);
   if (!rfh->IsRenderFrameLive())
     return;
-  if (rfh->IsCrossProcessSubframe() || !rfh->GetParent())
+  if (ShouldCreateDevToolsFor(rfh))
     result->push_back(RenderFrameDevToolsAgentHost::GetOrCreateFor(rfh));
 }
 
 // static
 bool DevToolsAgentHost::HasFor(WebContents* web_contents) {
   return FindAgentHost(web_contents) != NULL;
 }
 
 // static
 bool DevToolsAgentHost::IsDebuggerAttached(WebContents* web_contents) {
@@ skipping 175 matching lines @@
     RenderFrameHost* new_host) {
   if (old_host == render_frame_host_ && new_host != render_frame_host_) {
     // AboutToNavigateRenderFrame was not called for renderer-initiated
     // navigation.
     ReattachToRenderFrameHost(new_host);
   }
 }
 
 void
 RenderFrameDevToolsAgentHost::ReattachToRenderFrameHost(RenderFrameHost* rfh) {
+  if (!ShouldCreateDevToolsFor(rfh)) {
+    DestroyOnRenderFrameGone();
+    // |this| may be deleted at this point.
+    return;
+  }
+
   DCHECK(!reattaching_);
   reattaching_ = true;
   DisconnectRenderFrameHost();
   ConnectRenderFrameHost(rfh);
   reattaching_ = false;
 }
 
 void RenderFrameDevToolsAgentHost::FrameDeleted(RenderFrameHost* rfh) {
   if (rfh != render_frame_host_)
     return;
+  DestroyOnRenderFrameGone();
+  // |this| may be deleted at this point.
+}
 
+void RenderFrameDevToolsAgentHost::DestroyOnRenderFrameGone() {
   DCHECK(render_frame_host_);
   scoped_refptr<RenderFrameDevToolsAgentHost> protect(this);
   HostClosed();
   ClearRenderFrameHost();
   DevToolsManager::GetInstance()->AgentHostChanged(this);
   Release();
 }
 
 void RenderFrameDevToolsAgentHost::RenderProcessGone(
     base::TerminationStatus status) {
@@ skipping 74 matching lines @@
 void RenderFrameDevToolsAgentHost::Observe(int type,
                                           const NotificationSource& source,
                                           const NotificationDetails& details) {
   if (type == content::NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED) {
     bool visible = *Details<bool>(details).ptr();
     page_handler_->OnVisibilityChanged(visible);
   }
 }
 
 void RenderFrameDevToolsAgentHost::SetRenderFrameHost(RenderFrameHost* rfh) {
+  DCHECK(ShouldCreateDevToolsFor(rfh));
   DCHECK(!render_frame_host_);
   render_frame_host_ = static_cast<RenderFrameHostImpl*>(rfh);
-  // TODO(dgozman): here we should DCHECK that frame host is either root or
-  // cross process subframe, but this requires handling cross-process
-  // navigation. See http://crbug.com/464993.
 
   WebContentsObserver::Observe(WebContents::FromRenderFrameHost(rfh));
   RenderViewHostImpl* rvh = static_cast<RenderViewHostImpl*>(
       rfh->GetRenderViewHost());
   dom_handler_->SetRenderViewHost(rvh);
   emulation_handler_->SetRenderViewHost(rvh);
   input_handler_->SetRenderViewHost(rvh);
   network_handler_->SetRenderViewHost(rvh);
   page_handler_->SetRenderViewHost(rvh);
   service_worker_handler_->SetRenderFrameHost(render_frame_host_);
@@ skipping 110 matching lines @@
   if (!IsAttached() || !render_frame_host_)
     return;
   ProcessChunkedMessageFromAgent(message);
 }
 
 bool RenderFrameDevToolsAgentHost::IsChildFrame() {
   return render_frame_host_ && render_frame_host_->GetParent();
 }
 
 }  // namespace content