Add support for invoking the Windows 8 metro style hung renderer dialog box. The dialog box

chrome/browser/ui/views/hung_renderer_view_win.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/ui/views/hung_renderer_view_win.h"
 
+#include "base/win/metro.h"
+#include "chrome/browser/hang_monitor/hang_crash_dump_win.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/render_process_host.h"
+#include "grit/generated_resources.h"
+#include "ui/base/l10n/l10n_util.h"
+
+// Handler function type. This function is invoked when a button on the metro
+// dialog box is clicked.
+typedef void (*ButtonPressedHandler)();
+
+// Metro functions for displaying and dismissing a dialog box.
+typedef void (*MetroShowDialogBox)(const wchar_t* title,
+                                   const wchar_t* content,
+                                   const wchar_t* button1_label,
+                                   const wchar_t* button2_label,
+                                   ButtonPressedHandler button1_handler,
+                                   ButtonPressedHandler button2_handler);
+
+typedef void (*MetroDismissDialogBox)();
+
+using content::BrowserThread;
+
 // static
 HungRendererDialogView* HungRendererDialogView::Create() {
   if (!g_instance_)
     g_instance_ = new HungRendererDialogViewWin();
   return g_instance_;
 }
 
+HungRendererDialogViewWin::HungRendererDialogViewWin()
+    : contents_(NULL),
+      metro_dialog_displayed_(false) {
+}
+
+HungRendererDialogViewWin::~HungRendererDialogViewWin() {
+}
+
 void HungRendererDialogViewWin::ShowForWebContents(WebContents* contents) {
-  HungRendererDialogView::ShowForWebContents(contents);
+  if (!base::win::IsMetroProcess()) {

[sky, 2012/07/24 04:25:09]

There is no reason for subclassing here. Basically you have a big conditional.
If !metro do one thing, otherwise do something totally different. This
conditional should be up leveled to the create. I'm thinking something like:

void ShowHungRendererDialog(WebContents* contents) {
  if (ShowHungRendererDialogMetro(contents))
    return;
  // create HungRendererDialogView
}

#if !defined(OS_WIN)
bool ShowHungRendererDialogMetro(xxx) {
  return false;
#endif

In hung_renderer_dialog_view_win.cc:

bool ShowHungRendererDialogMetro(xxx) {
  if (IsMetro() && IsFrameActive()) {
    HungRendererDialogViewMetro::Show();
    return true;
  }
  return false;
}

Whatever hung_rendderer_dialog_view_win has in it does not subclass
HungRendererDialogView, it is its own class (or maybe just some functions, not
sure which makes more sense).

[ananta, 2012/07/24 18:43:48]

Done. The functionality to override the default hung renderer dialog is provided
via the functions PlatformShowCustomHungRendererDialog and
PlatformHideCustomHungRendererDialog

The functions return false by default to indicate that the default hang dialog
is to be shown. For metro we return true.

The functionality to display the metro dialog is provided by the new class
HungRendererDialogMetro

+    HungRendererDialogView::ShowForWebContents(contents);
+    return;
+  }
+  if (!metro_dialog_displayed_ && IsFrameActive(contents)) {
+    HMODULE metro_dll = base::win::GetMetroModule();
+    DCHECK(metro_dll);
+    if (metro_dll) {
+      MetroShowDialogBox show_dialog_box = reinterpret_cast<MetroShowDialogBox>
+          (::GetProcAddress(metro_dll, "ShowDialogBox"));
+      DCHECK(show_dialog_box);
+      if (show_dialog_box) {
+        string16 dialog_box_title =
+            l10n_util::GetStringUTF16(IDS_BROWSER_HANGMONITOR_RENDERER_TITLE);
+
+        string16 kill_button_label =
+            l10n_util::GetStringUTF16(IDS_BROWSER_HANGMONITOR_RENDERER_END);
+
+        string16 wait_button_label =
+            l10n_util::GetStringUTF16(IDS_BROWSER_HANGMONITOR_RENDERER_WAIT);
+
+        metro_dialog_displayed_ = true;
+
+        (*show_dialog_box)(dialog_box_title.c_str(),
+                           contents->GetTitle().c_str(),
+                           kill_button_label.c_str(),
+                           wait_button_label.c_str(),
+                           HungRendererDialogViewWin::OnMetroKillProcess,
+                           HungRendererDialogViewWin::OnMetroWait);
+      }
+    }
+  }
 }
 
 void HungRendererDialogViewWin::EndForWebContents(WebContents* contents) {
-  HungRendererDialogView::EndForWebContents(contents);
+  if (!base::win::IsMetroProcess()) {
+    HungRendererDialogView::EndForWebContents(contents);
+    return;
+  }
+  HMODULE metro_dll = base::win::GetMetroModule();
+  DCHECK(metro_dll);
+  if (metro_dll) {
+    MetroDismissDialogBox dismiss_dialog_box =
+        reinterpret_cast<MetroDismissDialogBox>
+            (::GetProcAddress(metro_dll, "DismissDialogBox"));
+    DCHECK(dismiss_dialog_box);
+    if (dismiss_dialog_box) {
+      (*dismiss_dialog_box)();
+      ResetMetroState();
+    }
+  }
 }
+
+void HungRendererDialogViewWin::ResetMetroState() {
+  metro_dialog_displayed_ = false;
+  contents_ = NULL;
+}
+
+// static
+void HungRendererDialogViewWin::OnMetroKillProcess() {
+  // Metro chrome will invoke these handlers on the metro thread. Ensure that
+  // we switch to the UI thread.
+  if (!BrowserThread::CurrentlyOn(BrowserThread::UI)) {
+    BrowserThread::PostTask(
+        BrowserThread::UI, FROM_HERE,
+        base::Bind(HungRendererDialogViewWin::OnMetroKillProcess));
+    return;
+  }
+
+  HungRendererDialogViewWin* instance =
+      static_cast<HungRendererDialogViewWin*>(GetInstance());
+  DCHECK(instance);
+  DCHECK(instance->contents_);
+
+  KillRendererProcess(
+      instance->contents_->GetRenderProcessHost()->GetHandle());
+
+  // The metro dialog box is dismissed when the button handlers are invoked.
+  instance->ResetMetroState();
+}
+
+// static
+void HungRendererDialogViewWin::OnMetroWait() {
+  // Metro chrome will invoke these handlers on the metro thread. Ensure that
+  // we switch to the UI thread.
+  if (!BrowserThread::CurrentlyOn(BrowserThread::UI)) {
+    BrowserThread::PostTask(
+        BrowserThread::UI, FROM_HERE,
+        base::Bind(HungRendererDialogViewWin::OnMetroWait));
+    return;
+  }
+  HungRendererDialogViewWin* instance =
+      static_cast<HungRendererDialogViewWin*>(GetInstance());
+  DCHECK(instance);
+  instance->ResetMetroState();
+}
+
+// static
+void HungRendererDialogView::KillRendererProcess(
+    base::ProcessHandle process_handle) {
+  // Try to generate a crash report for the hung process.
+  CrashDumpAndTerminateHungChildProcess(process_handle);
+}