Add UMA statistics to the clipboard

ui/base/clipboard/clipboard.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 "ui/base/clipboard/clipboard.h"
 
 #include <iterator>
 
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/metrics/histogram.h"
 #include "base/synchronization/lock.h"
 #include "ui/gfx/size.h"
 
 namespace ui {
 
 namespace {
 
 // A compromised renderer could send us bad data, so validate it.
 // This function only checks that the size parameter makes sense, the caller
 // is responsible for further validating the bitmap buffer against
@@ skipping 74 matching lines @@
 
 // The union serves to easily convert SourceTag into its binary representation
 // and vice versa.
 union SourceTag2BinaryHelper {
   Clipboard::SourceTag tag;
   uint8 bytes[kSourceTagSize];
 };
 
 }  // namespace
 
+const Clipboard::SourceTag Clipboard::kInvalidSourceTag =
+    reinterpret_cast<void*>(1);
 const char Clipboard::kMimeTypeText[] = "text/plain";
 const char Clipboard::kMimeTypeURIList[] = "text/uri-list";
 const char Clipboard::kMimeTypeDownloadURL[] = "downloadurl";
 const char Clipboard::kMimeTypeHTML[] = "text/html";
 const char Clipboard::kMimeTypeRTF[] = "text/rtf";
 const char Clipboard::kMimeTypePNG[] = "image/png";
 
 // static
 Clipboard::ObjectMapParam Clipboard::SourceTag2Binary(SourceTag tag) {
   SourceTag2BinaryHelper helper;
@@ skipping 63 matching lines @@
     clipboard_map->erase(it);
   }
 }
 
 void Clipboard::WriteObjects(Buffer buffer,
                              const ObjectMap& objects,
                              SourceTag tag) {
   WriteObjectsImpl(buffer, objects, tag);
   if (!write_objects_callback_.is_null())
     write_objects_callback_.Run(buffer);
+  ReportAction(buffer, tag == SourceTag() ? WRITE_CLIPBOARD_NO_SOURCE_TAG
+                                          : WRITE_CLIPBOARD_SOURCE_TAG);
 }
 
 void Clipboard::DispatchObject(ObjectType type, const ObjectMapParams& params) {
   // All types apart from CBF_WEBKIT need at least 1 non-empty param.
   if (type != CBF_WEBKIT && (params.empty() || params[0].empty()))
     return;
   // Some other types need a non-empty 2nd param.
   if ((type == CBF_BOOKMARK || type == CBF_BITMAP ||
        type == CBF_SMBITMAP || type == CBF_DATA) &&
       (params.size() != 2 || params[1].empty()))
@@ skipping 93 matching lines @@
       // We store the shared memory object pointer so it can be retrieved by the
       // UI thread (see DispatchObject()).
       iter->second[0].clear();
       for (size_t i = 0; i < sizeof(SharedMemory*); ++i)
         iter->second[0].push_back(reinterpret_cast<char*>(&bitmap)[i]);
       has_shared_bitmap = true;
     }
   }
 }
 
+void Clipboard::ReportAction(Buffer buffer, TrackedAction action) const
+{
+  if (buffer != BUFFER_STANDARD)
+    return;
+
+  switch (action) {
+    case WRITE_CLIPBOARD_NO_SOURCE_TAG:
+    case WRITE_CLIPBOARD_SOURCE_TAG:
+      UMA_HISTOGRAM_ENUMERATION("Clipboard.IncognitoUseCase",
+                                action,
+                                MAX_TRACKED_ACTION);
+      break;
+    // The code below counts cases when there is the kInvalidSourceTag in the
+    // clipboard. That is, original data came from Incognito window and was
+    // destroyed with that window.
+    case READ_TEXT:
+      if (kInvalidSourceTag == ReadSourceTag(buffer)) {
+        UMA_HISTOGRAM_ENUMERATION("Clipboard.IncognitoUseCase",
+                                  action,
+                                  MAX_TRACKED_ACTION);
+      }
+      break;
+    case MAX_TRACKED_ACTION:
+      break;
+  }
+}
+
 }  // namespace ui