Add Keyboard Latency UMA Metrics.

content/public/browser/render_widget_host.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_PUBLIC_BROWSER_RENDER_WIDGET_HOST_H_
 #define CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_H_
 
 #include <stdint.h>
 
 #include "base/callback.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/native_web_keyboard_event.h"
 #include "content/public/common/drop_data.h"
 #include "ipc/ipc_channel.h"
 #include "ipc/ipc_sender.h"
 #include "third_party/WebKit/public/platform/WebDragOperation.h"
 #include "third_party/WebKit/public/platform/WebGestureEvent.h"
 #include "third_party/WebKit/public/platform/WebInputEvent.h"
 #include "third_party/WebKit/public/web/WebTextDirection.h"
+#include "ui/events/latency_info.h"

[mfomitchev, 2017/04/04 14:59:06]

Declare instead of including in .h.

[tdresser, 2017/05/01 15:49:21]

Done.

 #include "ui/gfx/geometry/size.h"
 #include "ui/surface/transport_dib.h"
 
 namespace blink {
 class WebMouseEvent;
 class WebMouseWheelEvent;
 }
 
 namespace content {
 
@@ skipping 126 matching lines @@
   // window will show active controls even if the focus is not in the web
   // contents, but e.g. in the omnibox.
   virtual void SetActive(bool active) = 0;
 
   // Forwards the given message to the renderer. These are called by
   // the view when it has received a message.
   virtual void ForwardMouseEvent(
       const blink::WebMouseEvent& mouse_event) = 0;
   virtual void ForwardWheelEvent(
       const blink::WebMouseWheelEvent& wheel_event) = 0;
-  virtual void ForwardKeyboardEvent(
-      const NativeWebKeyboardEvent& key_event) = 0;
+  virtual void ForwardKeyboardEventWithLatencyInfo(

[mfomitchev, 2017/04/04 14:59:06]

With other events we only have "WithLatencyInfo" variants in RWHImpl. Is there a
reason to break the pattern for key events? This also means we have to create
dummy LatencyInfo objects in a bunch of places instead of in once common place. 

[tdresser, 2017/05/01 15:49:21]

This is only required for FindBarHost, which has a native key event (with
LatencyInfo), and then wants to forward the event via the RWH.

We could have both methods here?

[mfomitchev, 2017/05/04 20:36:05]

Could FindBarHost do  RenderWidgetHostImpl::From()? Either way, I think it would
make sense to keep ForwardKeyboardEvent here, and have it create the LatencyInfo
object and call ForwardKeyboardEventWithLatencyInfo similar to other
ForwardXYZEvent variants. 

We are creating LatencyInfo for this method in vr_input_manager.cc,
autofill_interactive_uitest.cc, password_generation_interactive_uitest.cc,
input_handler.cc, render_widget_host_view_guest.cc,
render_widget_host_unittest.cc, render_widget_host_view_android.cc, etc. So
there's quite a bit of duplication which would be nice to get rid of.

[tdresser, 2017/05/09 15:29:25]

FindBarHost can't access RenderWidgetHostImpl due to DEPS, which I think are
probably correct.

I could add both methods to RWH?

[mfomitchev, 2017/05/09 17:35:23]

I see. That sounds reasonable to me - at least we'll get rid of the code
duplication.

[tdresser, 2017/05/10 14:27:15]

Done.

+      const NativeWebKeyboardEvent& key_event,
+      const ui::LatencyInfo& latency) = 0;
   virtual void ForwardGestureEvent(
       const blink::WebGestureEvent& gesture_event) = 0;
 
   virtual RenderProcessHost* GetProcess() const = 0;
 
   virtual int GetRoutingID() const = 0;
 
   // Gets the View of this RenderWidgetHost. Can be nullptr, e.g. if the
   // RenderWidget is being destroyed or the render process crashed. You should
   // never cache this pointer since it can become nullptr if the renderer
@@ skipping 83 matching lines @@
   // This allows the renderer to reset some state.
   virtual void DragSourceSystemDragEnded() {};
 
   // Filters drop data before it is passed to RenderWidgetHost.
   virtual void FilterDropData(DropData* drop_data) {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_H_