Implement function that hides the WebUI Hung Renderer Dialog.

chrome/browser/ui/webui/hung_renderer_dialog.cc

 // Copyright (c) 2011 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/ui/webui/hung_renderer_dialog.h"
 
 #include <string>
 #include <vector>
 
 #include "base/json/json_reader.h"
 #include "base/values.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_list.h"
 #include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
 #include "chrome/common/logging_chrome.h"
 #include "chrome/common/url_constants.h"
 #include "content/browser/renderer_host/render_view_host.h"
 #include "content/browser/tab_contents/tab_contents.h"
 #include "content/common/result_codes.h"
 #include "grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util.h"
+#include "views/widget/widget.h"
 
 namespace {
 HungRendererDialog* g_instance = NULL;
 const int kHungRendererDialogWidth = 425;
 const int kHungRendererDialogHeight = 200;
 }
 
 namespace browser {
 
 void ShowHungRendererDialog(TabContents* contents) {
   if (!logging::DialogsAreSuppressed()) {
     if (!g_instance) {
       g_instance = new HungRendererDialog();
     } else {
       NOTIMPLEMENTED() << " ShowHungRendererDialog called twice.";

[flackr, 2011/09/03 17:51:31]

This was the case that you said can occur if another renderer hangs while the
dialog is up right? I know the GTK hung renderer dialog didn't handle this but
if it can occur you should at least leave a TODO to either support showing more
than one hung renderer in one dialog or allow more than one dialog to be shown
if other renderers hang.

[wyck, 2011/09/06 18:07:35]

Now that 'hide' is implemented, this doesn't happen.

       return;
     }
     g_instance->ShowDialog(NULL, contents);
   }
 }
 
 void HideHungRendererDialog(TabContents* contents) {
-  if (!logging::DialogsAreSuppressed() && g_instance) {
-    // TODO(wyck): Hide the webui hung renderer dialog.
-    NOTIMPLEMENTED() << " TODO: Hide the webui hung renderer dialog.";
-  }
+  if (!logging::DialogsAreSuppressed() && g_instance)
+    g_instance->HideDialog(contents);
 }
 
 }  // namespace browser
 
 ////////////////////////////////////////////////////////////////////////////////
 // HungRendererDialog methods
 
 HungRendererDialog::HungRendererDialog()
-    : contents_(NULL) {
+    : contents_(NULL),
+      window_(NULL) {
 }
 
 void HungRendererDialog::ShowDialog(gfx::NativeWindow owning_window,
                                     TabContents* contents) {
   DCHECK(contents);
   contents_ = contents;
   Browser* browser = BrowserList::GetLastActive();
   DCHECK(browser);
-  browser->BrowserShowHtmlDialog(this, owning_window);
+  window_ = browser->BrowserShowHtmlDialog(this, owning_window);
+}
+
+void HungRendererDialog::HideDialog(TabContents* contents) {

[flackr, 2011/09/03 17:51:31]

You should check that (contents_->GetRenderProcessHost() ==
contents->GetRenderProcessHost()) to be sure HideDialog call was for this hung
renderer.

[wyck, 2011/09/06 18:07:35]

Done.

+  // Settings |contents_| to NULL prevents the hang monitor from restarting.
+  contents_ = NULL;
+  views::Widget* widget = views::Widget::GetWidgetForNativeWindow(window_);
+  DCHECK(widget);
+  widget->Close();
 }
 
 bool HungRendererDialog::IsDialogModal() const {
   return false;
 }
 
 string16 HungRendererDialog::GetDialogTitle() const {
   return l10n_util::GetStringUTF16(IDS_BROWSER_HANGMONITOR_RENDERER_TITLE);
 }
 
@@ skipping 11 matching lines @@
 }
 
 std::string HungRendererDialog::GetDialogArgs() const {
   return std::string();  // There are no args used.
 }
 
 void HungRendererDialog::OnDialogClosed(const std::string& json_retval) {
   // Figure out what the response was.
   scoped_ptr<Value> root(base::JSONReader::Read(json_retval, false));
   bool response = false;
-  ListValue* list;
-  if (!root.get() || !root->GetAsList(&list) || !list ||
-      !list->GetBoolean(0, &response)) {
-    NOTREACHED() << "json does not describe a valid result";
-  }
-
-  if (response) {
+  ListValue* list = NULL;

[wyck, 2011/09/02 19:18:43]

Decided to initialize this too.

+  // If the dialog closes because of a button click then the json is a list
+  // containing a single bool.  If the dialog closes some other way, then we
+  // assume it means no permission was given to kill tabs.
+  if (root.get() && root->GetAsList(&list) && list &&

[wyck, 2011/09/02 19:18:43]

Folded into one statement.

+      list->GetBoolean(0, &response) && response) {

[flackr, 2011/09/03 17:51:31]

Why not use the result from list->GetBoolean to know if the user pressed wait or
not rather than set contents_ to NULL in HideDialog. i.e.
  if (root.get() && root->GetAsList(&list) && list &&
      list->GetBoolean(0, &response)) {
    if (response)
      // Kill process.
    else
      // Restart timer.

[wyck, 2011/09/06 18:07:35]

Because if you click the X on the dialog, it closes with no response, which is
to be interpreted as "do the default action (wait)".  But if you kill the
dialog, it also closes with no response, which is to be interpreted as "do
nothing."  So rather than set a flag in the class indicating that it is being
closed externally rather than by the user, I clear the contents_ member variable
(which serves as such a flag.)

That's what the comment on line 69 is getting at.

     // The user indicated that it is OK to kill the renderer process.
     if (contents_ && contents_->GetRenderProcessHost()) {
       base::KillProcess(contents_->GetRenderProcessHost()->GetHandle(),
                         content::RESULT_CODE_HUNG, false);
     }
   } else {
     // No indication from the user that it is ok to kill anything. Just wait.
     // Start waiting again for responsiveness.
     if (contents_ && contents_->render_view_host())
       contents_->render_view_host()->RestartHangMonitorTimeout();
   }
-
   g_instance = NULL;
   delete this;
 }
 
 void HungRendererDialog::OnCloseContents(TabContents* source,
                      bool* out_close_dialog) {
   NOTIMPLEMENTED();
 }
 
 bool HungRendererDialog::ShouldShowDialogTitle() const {
@@ skipping 27 matching lines @@
       DictionaryValue* dict = new DictionaryValue();
       dict->SetString("url", it->tab_contents()->GetURL().spec());
       dict->SetString("title", title);
       tab_contents_list.Append(dict);
     }
   }
   // Send list of tab contents details to javascript.
   web_ui_->CallJavascriptFunction("hungRendererDialog.setTabContentsList",
                                   tab_contents_list);
 }
-