Add an histogram to differentiate between hang types of the renderer

content/browser/web_contents/web_contents_impl.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/web_contents/web_contents_impl.h"
 
 #include <stddef.h>
 
 #include <cmath>
 #include <utility>
@@ skipping 4615 matching lines @@
   if (rdh && type != blink::WebInputEvent::MouseWheel)
     rdh->OnUserGesture();
 }
 
 void WebContentsImpl::OnIgnoredUIEvent() {
   // Notify observers.
   FOR_EACH_OBSERVER(WebContentsObserver, observers_, DidGetIgnoredUIEvent());
 }
 
 void WebContentsImpl::RendererUnresponsive(
-    RenderWidgetHostImpl* render_widget_host) {
+    RenderWidgetHostImpl* render_widget_host,
+    RenderWidgetHostDelegate::RendererUnresponsiveType type) {
   FOR_EACH_OBSERVER(WebContentsObserver, observers_,
                     OnRendererUnresponsive(render_widget_host));
 
   // Don't show hung renderer dialog for a swapped out RVH.
   if (render_widget_host != GetRenderViewHost()->GetWidget())
     return;
 
   RenderFrameHostImpl* rfhi =
       static_cast<RenderFrameHostImpl*>(GetRenderViewHost()->GetMainFrame());
 
   // Ignore renderer unresponsive event if debugger is attached to the tab
   // since the event may be a result of the renderer sitting on a breakpoint.
   // See http://crbug.com/65458
   if (DevToolsAgentHost::IsDebuggerAttached(this))
     return;
 
+  // Record histograms about the type of renderer hang.
+  UMA_HISTOGRAM_ENUMERATION(
+      "ChildProcess.HangRendererType", type,
+      RenderWidgetHostDelegate::RENDERER_UNRESPONSIVE_MAX);
+
   // We might have been waiting for both beforeunload and unload ACK.
   // Check if tab is to be unloaded first.
   if (rfhi->IsWaitingForUnloadACK()) {
     // Hang occurred while firing the unload handler.
     // Pretend the handler fired so tab closing continues as if it had.
     GetRenderViewHost()->set_sudden_termination_allowed(true);
 
     if (!GetRenderManager()->ShouldCloseTabOnUnresponsiveRenderer())
       return;
 
@@ skipping 507 matching lines @@
   for (RenderViewHost* render_view_host : render_view_host_set)
     render_view_host->OnWebkitPreferencesChanged();
 }
 
 void WebContentsImpl::SetJavaScriptDialogManagerForTesting(
     JavaScriptDialogManager* dialog_manager) {
   dialog_manager_ = dialog_manager;
 }
 
 }  // namespace content