Add an histogram to differentiate between hang types of the renderer

content/browser/renderer_host/render_widget_host_impl.h

 // 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.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 13 matching lines @@
 #include "base/time/time.h"
 #include "base/timer/elapsed_timer.h"
 #include "build/build_config.h"
 #include "cc/resources/shared_bitmap.h"
 #include "content/browser/renderer_host/event_with_latency_info.h"
 #include "content/browser/renderer_host/input/input_ack_handler.h"
 #include "content/browser/renderer_host/input/input_router_client.h"
 #include "content/browser/renderer_host/input/render_widget_host_latency_tracker.h"
 #include "content/browser/renderer_host/input/synthetic_gesture.h"
 #include "content/browser/renderer_host/input/touch_emulator_client.h"
+#include "content/browser/renderer_host/render_widget_host_delegate.h"
 #include "content/browser/renderer_host/render_widget_host_view_base.h"
 #include "content/common/input/input_event_ack_state.h"
 #include "content/common/input/synthetic_gesture_packet.h"
 #include "content/common/view_message_enums.h"
 #include "content/public/browser/readback_types.h"
 #include "content/public/browser/render_widget_host.h"
 #include "content/public/common/page_zoom.h"
 #include "ipc/ipc_listener.h"
 #include "third_party/WebKit/public/platform/WebDisplayMode.h"
 #include "ui/base/ime/text_input_mode.h"
@@ skipping 32 matching lines @@
 
 namespace gfx {
 class Range;
 }
 
 namespace content {
 
 class BrowserAccessibilityManager;
 class InputRouter;
 class MockRenderWidgetHost;
-class RenderWidgetHostDelegate;
 class RenderWidgetHostOwnerDelegate;
 class SyntheticGestureController;
 class TimeoutMonitor;
 class TouchEmulator;
 class WebCursor;
 struct EditCommand;
 struct ResizeParams;
 struct TextInputState;
 
 // This implements the RenderWidgetHost interface that is exposed to
@@ skipping 183 matching lines @@
   bool resize_ack_pending_for_testing() { return resize_ack_pending_; }
 
   // GPU accelerated version of GetBackingStore function. This will
   // trigger a re-composite to the view. It may fail if a resize is pending, or
   // if a composite has already been requested and not acked yet.
   bool ScheduleComposite();
 
   // Starts a hang monitor timeout. If there's already a hang monitor timeout
   // the new one will only fire if it has a shorter delay than the time
   // left on the existing timeouts.
-  void StartHangMonitorTimeout(base::TimeDelta delay);
+  void StartHangMonitorTimeout(
+      base::TimeDelta delay,
+      RenderWidgetHostDelegate::RendererUnresponsiveType type);

[nasko, 2016/07/12 17:18:02]

Shouldn't this be the hang monitor reason or type? Unresponsive is a state that
is gotten into later on, not at the start of the monitor.

[clamy, 2016/07/13 10:02:22]

Done.

 
   // Stops all existing hang monitor timeouts and assumes the renderer is
   // responsive.
   void StopHangMonitorTimeout();
 
   // Starts the rendering timeout, which will clear displayed graphics if
   // a new compositor frame is not received before it expires.
   void StartNewContentRenderingTimeout();
 
   // Notification that a new compositor frame has been generated following
@@ skipping 509 matching lines @@
 
   // Indicates whether this RenderWidgetHost thinks is focused. This is trying
   // to match what the renderer process knows. It is different from
   // RenderWidgetHostView::HasFocus in that in that the focus request may fail,
   // causing HasFocus to return false when is_focused_ is true.
   bool is_focused_;
 
   // This value indicates how long to wait before we consider a renderer hung.
   base::TimeDelta hung_renderer_delay_;
 
+  // Stores the reason the hang_monitor_timeout_ i sbeing used, to report

[nasko, 2016/07/12 17:18:03]

nit: "is being" or "has been started. Used to ..."

[clamy, 2016/07/13 10:02:21]

Done.

+  // histograms if the renderer is hung.
+  RenderWidgetHostDelegate::RendererUnresponsiveType hang_type_;

[nasko, 2016/07/12 17:18:02]

nit: hang_monitor_type_ or hang_monitor_reason_?

[clamy, 2016/07/13 10:02:22]

Done.

+
   // This value indicates how long to wait for a new compositor frame from a
   // renderer process before clearing any previously displayed content.
   base::TimeDelta new_content_rendering_delay_;
 
 #if defined(OS_MACOSX)
   std::unique_ptr<device::PowerSaveBlocker> power_save_blocker_;
 #endif
 
   base::WeakPtrFactory<RenderWidgetHostImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_