[Android] Add support for a hung renderer dialog

chrome/browser/android/hung_renderer_infobar_delegate.cc

+// Copyright 2015 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/android/hung_renderer_infobar_delegate.h"
+
+#include "base/callback.h"
+#include "base/metrics/histogram.h"
+#include "base/metrics/user_metrics.h"
+#include "chrome/grit/generated_resources.h"
+#include "components/infobars/core/infobar.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/browser/web_contents.h"
+#include "content/public/common/result_codes.h"
+#include "grit/theme_resources.h"
+#include "ui/base/l10n/l10n_util.h"
+
+HungRendererInfoBarDelegate::HungRendererInfoBarDelegate(
+    content::WebContents* web_contents)
+    : web_contents_(web_contents), action_logged_for_uma_(false) {
+  DCHECK(web_contents);
+}
+
+HungRendererInfoBarDelegate::~HungRendererInfoBarDelegate() {
+  LogAction(REMOVE);
+}
+
+void HungRendererInfoBarDelegate::InfoBarDismissed() {
+  LogAction(DISMISS);
+}
+
+HungRendererInfoBarDelegate*
+HungRendererInfoBarDelegate::AsHungRendererInfoBarDelegate() {
+  return this;
+}
+
+int HungRendererInfoBarDelegate::GetIconID() const {
+  return IDR_INFOBAR_FROZEN_TAB;
+}
+
+base::string16 HungRendererInfoBarDelegate::GetMessageText() const {
+  return l10n_util::GetPluralStringFUTF16(IDS_BROWSER_HANGMONITOR_RENDERER, 1);
+}
+
+base::string16 HungRendererInfoBarDelegate::GetButtonLabel(
+    InfoBarButton button) const {
+  return l10n_util::GetStringUTF16((button == BUTTON_OK)
+                                       ? IDS_BROWSER_HANGMONITOR_RENDERER_END
+                                       : IDS_BROWSER_HANGMONITOR_RENDERER_WAIT);
+}
+
+bool HungRendererInfoBarDelegate::Accept() {
+  LogAction(KILL);
+  content::RenderProcessHost* process = web_contents_->GetRenderProcessHost();
+  process->Shutdown(content::RESULT_CODE_HUNG, false);
+  return true;
+}
+
+bool HungRendererInfoBarDelegate::Cancel() {
+  LogAction(WAIT);
+  return true;
+}
+
+void HungRendererInfoBarDelegate::OnRendererResponsive() {
+  LogAction(RESPONSIVE);
+}
+
+void HungRendererInfoBarDelegate::LogAction(Action action) {
+  if (action_logged_for_uma_)
+    return;
+
+  action_logged_for_uma_ = true;
+
+  UMA_HISTOGRAM_ENUMERATION("HungRenderer.MobileInfoBar.Action", action,
+                            ACTION_COUNT);
+
+  if (action == KILL) {
+    base::RecordAction(
+        base::UserMetricsAction("MobileHungRendererInfoBarKill"));

[gone, 2015/09/01 18:49:34]

Any reason you're doubling up on the count and histogram?  Seems like the
histogram should have all the information you'd get from a count.

[jdduke (slow), 2015/09/01 21:49:20]

Yeah, I thought it might be nice to have this included in all the other fun user
metrics so you can compare frequency of killing to say, refreshing. But it's not
really necessary. I'll remove it.

+  }
+}