Track plugin input event latency

ppapi/proxy/plugin_globals.h

Index: ppapi/proxy/plugin_globals.h
diff --git a/ppapi/proxy/plugin_globals.h b/ppapi/proxy/plugin_globals.h
index 5dc614d239bd72f24e84a11b9fd8290f72facdf8..7680a6e8880d257a7f60cd87690d5c5c0600412d 100644
--- a/ppapi/proxy/plugin_globals.h
+++ b/ppapi/proxy/plugin_globals.h
@@ -5,7 +5,9 @@
 #ifndef PPAPI_PROXY_PLUGIN_GLOBALS_H_
 #define PPAPI_PROXY_PLUGIN_GLOBALS_H_
 
+#include <map>
 #include <string>
+#include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
@@ -16,6 +18,7 @@
 #include "ppapi/proxy/ppapi_proxy_export.h"
 #include "ppapi/shared_impl/callback_tracker.h"
 #include "ppapi/shared_impl/ppapi_globals.h"
+#include "ui/events/latency_info.h"
 
 namespace base {
 class Thread;
@@ -134,6 +137,17 @@ class PPAPI_PROXY_EXPORT PluginGlobals : public PpapiGlobals {
     return resource_reply_thread_registrar_.get();
   }
 
+  // Cache a input event's |latency_info| for the plugin |instance|.
+  void AddLatencyInfo(ui::LatencyInfo latency_info, PP_Instance instance);

[piman, 2014/04/25 01:59:43]

How about stashing all this state/logic on the InstanceData instead?

[Yufeng Shen (Slow to review), 2014/04/25 20:42:42]

All the logic/data are now moved to the host side.

+  // Upon graphics invalidation, input events are considered to have caused
+  // rendering damage, their cached latency_info should continue to track
+  // the new plugin output frame until it reaches screen.
+  void OnGraphicsInvalidation(PP_Instance instance);
+  // On graphics flush, the cached latency_info are passed into |latency_info|
+  // if they are associated with rendering damage, or terminated if not.
+  void OnGraphicsFlush(std::vector<ui::LatencyInfo>* latency_info,
+                       PP_Instance instance);
+
   // Interval to limit how many IPC messages are sent indicating that the plugin
   // is active and should be kept alive. The value must be smaller than any
   // threshold used to kill inactive plugins by the embedder host.
@@ -184,6 +198,11 @@ class PPAPI_PROXY_EXPORT PluginGlobals : public PpapiGlobals {
 
   unsigned keepalive_throttle_interval_milliseconds_;
 
+  // Input event latency that are not associated with any output frame yet.
+  std::map<PP_Instance, std::vector<ui::LatencyInfo> > pending_latency_info_;
+  // Input event latency that are associated with next output frame.
+  std::map<PP_Instance, std::vector<ui::LatencyInfo> > latency_info_for_frame_;
+
   // Member variables should appear before the WeakPtrFactory, see weak_ptr.h.
   base::WeakPtrFactory<PluginGlobals> weak_factory_;