[DevTools] Fix crash in DevToolsWindow::Create

chrome/browser/devtools/devtools_window.cc

Index: chrome/browser/devtools/devtools_window.cc
diff --git a/chrome/browser/devtools/devtools_window.cc b/chrome/browser/devtools/devtools_window.cc
index f3c189c5b82d8615e021f3621d2962281e9f2442..2a01777cfe3f43aa4dd9e0980a37971ccb6c0e4d 100644
--- a/chrome/browser/devtools/devtools_window.cc
+++ b/chrome/browser/devtools/devtools_window.cc
@@ -394,7 +394,8 @@ DevToolsWindow* DevToolsWindow::OpenDevToolsWindowForWorker(
   DevToolsWindow* window = FindDevToolsWindow(worker_agent.get());
   if (!window) {
     window = DevToolsWindow::CreateDevToolsWindowForWorker(profile);
-    window->bindings_->AttachTo(worker_agent);
+    if (window)
+      window->bindings_->AttachTo(worker_agent);
   }
   window->ScheduleShow(DevToolsToggleAction::Show());
   return window;
@@ -445,9 +446,10 @@ void DevToolsWindow::OpenExternalFrontend(
     bool isWorker) {
   DevToolsWindow* window = FindDevToolsWindow(agent_host.get());
   if (!window) {
-    window = Create(profile, GURL(), NULL, isWorker,
+    window = Create(profile, GURL(), nullptr, isWorker,
                     DevToolsUI::GetProxyURL(frontend_url).spec(), false, "");
-    window->bindings_->AttachTo(agent_host);
+    if (window)

[dgozman, 2015/01/29 15:50:35]

Let's only |if (window)| in this method, and |DCHECK(window)| in all other
places.

[vkuzkokov, 2015/01/30 12:44:15]

Done.

+      window->bindings_->AttachTo(agent_host);
   }
   window->ScheduleShow(DevToolsToggleAction::Show());

[dgozman, 2015/01/29 15:50:35]

This |window| may be nullptr.

[vkuzkokov, 2015/01/30 12:44:15]

Done.

 }
@@ -469,6 +471,8 @@ DevToolsWindow* DevToolsWindow::ToggleDevToolsWindow(
         base::UserMetricsAction("DevTools_InspectRenderer"));
     window = Create(profile, GURL(), inspected_web_contents,
                     false, std::string(), true, settings);
+    if (!window)
+      return nullptr;
     window->bindings_->AttachTo(agent.get());
     do_open = true;
   }
@@ -499,7 +503,7 @@ void DevToolsWindow::InspectElement(
   // TODO(loislo): we should initiate DevTools window opening from within
   // renderer. Otherwise, we still can hit a race condition here.
   DevToolsWindow* window = OpenDevToolsWindow(inspected_web_contents);
-  if (should_measure_time)
+  if (window && should_measure_time)
     window->inspect_element_start_time_ = start_time;
 }
 
@@ -672,7 +676,8 @@ DevToolsWindow::DevToolsWindow(Profile* profile,
       ui::PAGE_TRANSITION_AUTO_TOPLEVEL, std::string());
 
   bindings_ = DevToolsUIBindings::ForWebContents(main_web_contents_);
-  DCHECK(bindings_);
+  if (!bindings_)
+    return;
 
   // Bindings take ownership over devtools as its delegate.
   bindings_->SetDelegate(this);
@@ -727,7 +732,13 @@ DevToolsWindow* DevToolsWindow::Create(
                           shared_worker_frontend,
                           remote_frontend,
                           can_dock, settings));
-  return new DevToolsWindow(profile, url, inspected_web_contents, can_dock);
+  DevToolsWindow* window =
+      new DevToolsWindow(profile, url, inspected_web_contents, can_dock);
+  if (!window->bindings_) {

[pfeldman, 2015/01/29 16:09:59]

Why is this happening? It makes code so much more complex.

[vkuzkokov, 2015/01/30 12:44:14]

DevToolsUI might be not created for some reason. Bad frontend_url from
remote device would do the trick.

+    delete window;
+    window = nullptr;
+  }
+  return window;
 }
 
 // static