Pepper: Log in UMA when an interface is used.

content/browser/renderer_host/pepper/browser_ppapi_host_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/renderer_host/pepper/browser_ppapi_host_impl.h"
 
+#include "base/metrics/sparse_histogram.h"
 #include "content/browser/renderer_host/pepper/pepper_message_filter.h"
 #include "content/browser/tracing/trace_message_filter.h"
 #include "content/common/pepper_renderer_instance_data.h"
 #include "content/public/common/process_type.h"
 #include "ipc/ipc_message_macros.h"
 #include "ppapi/proxy/ppapi_messages.h"
 
 namespace content {
 
 // static
@@ skipping 140 matching lines @@
 bool BrowserPpapiHostImpl::HostMessageFilter::OnMessageReceived(
     const IPC::Message& msg) {
   // Don't forward messages if our owner object has been destroyed.
   if (!ppapi_host_)
     return false;
 
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(BrowserPpapiHostImpl::HostMessageFilter, msg)
     // Add necessary message handlers here.
     IPC_MESSAGE_HANDLER(PpapiHostMsg_Keepalive, OnKeepalive)
+    IPC_MESSAGE_HANDLER(PpapiHostMsg_LogInterfaceUsage,
+                        OnHostMsgLogInterfaceUsage)
     IPC_MESSAGE_UNHANDLED(handled = ppapi_host_->OnMessageReceived(msg))
   IPC_END_MESSAGE_MAP();
   return handled;
 }
 
 void BrowserPpapiHostImpl::HostMessageFilter::OnHostDestroyed() {
   DCHECK(ppapi_host_);
   ppapi_host_ = NULL;
   browser_ppapi_host_impl_ = NULL;
 }
 
 BrowserPpapiHostImpl::HostMessageFilter::~HostMessageFilter() {
 }
 
 void BrowserPpapiHostImpl::HostMessageFilter::OnKeepalive() {
   if (browser_ppapi_host_impl_)
     browser_ppapi_host_impl_->OnKeepalive();
 }
 
+void BrowserPpapiHostImpl::HostMessageFilter::OnHostMsgLogInterfaceUsage(
+    int hash) const {
+  UMA_HISTOGRAM_SPARSE_SLOWLY("Pepper.InterfaceUsed", hash);
+}
+
 void BrowserPpapiHostImpl::OnKeepalive() {
   // An instance has been active. The on_keepalive_callback_ will be
   // used to permit the content embedder to handle this, e.g. by tracking
   // activity and shutting down processes that go idle.
   //
   // Currently embedders do not need to distinguish between instances having
   // different idle state, and thus this implementation handles all instances
   // for this module together.
 
   if (on_keepalive_callback_.is_null())
     return;
 
   BrowserPpapiHost::OnKeepaliveInstanceData
       instance_data(instance_map_.size());
 
   InstanceMap::iterator instance = instance_map_.begin();
   int i = 0;
   while (instance != instance_map_.end()) {
     instance_data[i].render_process_id = instance->second.render_process_id;
     instance_data[i].render_frame_id = instance->second.render_frame_id;
     instance_data[i].document_url = instance->second.document_url;
     ++instance;
     ++i;
   }
   on_keepalive_callback_.Run(instance_data, profile_data_directory_);
 }
 
 }  // namespace content