Record time interval between clipboard data commit and data read.

Will be used by PMs to analyze user behavior on CrOS in light of new
clipboard data requirements coming from Android.

Note that the histogram added in this CL is only implemented for CrOS'
`ClipboardNonBacked` clipboard implementation.

Bug: 1310400
Change-Id: I63fbb8fa70ddb36c580ed71abc97fb1ab42c7325
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3553622
Reviewed-by: Austin Sullivan <asully@chromium.org>
Reviewed-by: Ayu Ishii <ayui@chromium.org>
Commit-Queue: David Black <dmblack@google.com>
Cr-Commit-Position: refs/heads/main@{#987040}

ash/clipboard/clipboard_history_controller_impl.cc

@@ -729,6 +729,7 @@ void ClipboardHistoryControllerImpl::PasteClipboardHistoryItem(
     if (paste_plain_text) {
       // When the shift key is pressed, we only paste plain text.
       temp_data = std::make_unique<ui::ClipboardData>();
+      temp_data->set_commit_time(item.data().commit_time());
       temp_data->set_text(item.data().text());
       ui::DataTransferEndpoint* data_src = item.data().source();
       if (data_src) {

tools/metrics/histograms/metadata/storage/histograms.xml

@@ -113,6 +113,19 @@ chromium-metrics-reviews@google.com.
   </summary>
 </histogram>
 
+<histogram name="Clipboard.TimeIntervalBetweenCommitAndRead" units="ms"
+    expires_after="2022-09-25">
+  <owner>dcheng@chromium.org</owner>
+  <owner>src/ui/base/clipboard/OWNERS</owner>
+  <summary>
+    Records the time interval between when clipboard data was committed to the
+    clipboard and the same clipboard data was read from the clipboard. The same
+    clipboard data may be read multiple times. Emitted at the moment the
+    clipboard data was read. Currently only implemented for Chrome OS' in-memory
+    clipboard (`ui::ClipboardNonBacked`).
+  </summary>
+</histogram>
+
 <histogram name="Clipboard.Write" enum="ClipboardFormatWrite"
     expires_after="2022-08-07">
   <owner>huangdarwin@chromium.org</owner>

ui/base/clipboard/clipboard_data.cc

@@ -49,6 +49,9 @@ ClipboardData::ClipboardData(const ClipboardData& other) {
   filenames_ = other.filenames_;
   src_ = other.src_ ? std::make_unique<DataTransferEndpoint>(*other.src_.get())
                     : nullptr;
+#if BUILDFLAG(IS_CHROMEOS)
+  commit_time_ = other.commit_time_;
+#endif  // BUILDFLAG(IS_CHROMEOS)
 }
 
 ClipboardData::~ClipboardData() = default;

ui/base/clipboard/clipboard_data.h

@@ -14,6 +14,10 @@
 #include "ui/base/clipboard/file_info.h"
 #include "ui/base/data_transfer_policy/data_transfer_endpoint.h"
 
+#if BUILDFLAG(IS_CHROMEOS)
+#include "base/time/time.h"
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
 class SkBitmap;
 
 namespace ui {
@@ -151,6 +155,13 @@ class COMPONENT_EXPORT(UI_BASE_CLIPBOARD) ClipboardData {
     src_ = std::move(src);
   }
 
+#if BUILDFLAG(IS_CHROMEOS)
+  absl::optional<base::Time> commit_time() const { return commit_time_; }
+  void set_commit_time(absl::optional<base::Time> commit_time) {
+    commit_time_ = commit_time;
+  }
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
  private:
   // Plain text in UTF8 format.
   std::string text_;
@@ -197,6 +208,11 @@ class COMPONENT_EXPORT(UI_BASE_CLIPBOARD) ClipboardData {
 
   // The source of the data.
   std::unique_ptr<DataTransferEndpoint> src_;
+
+#if BUILDFLAG(IS_CHROMEOS)
+  // If present, the time at which this data was committed to the clipboard.
+  absl::optional<base::Time> commit_time_;
+#endif  // BUILDFLAG(IS_CHROMEOS)
 };
 
 }  // namespace ui

ui/base/clipboard/clipboard_metrics.cc

@@ -7,6 +7,10 @@
 #include "base/metrics/histogram_functions.h"
 #include "base/metrics/histogram_macros.h"
 
+#if BUILDFLAG(IS_CHROMEOS)
+#include "ui/base/clipboard/clipboard_data.h"
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
 namespace ui {
 
 void RecordRead(ClipboardFormatMetric metric) {
@@ -17,4 +21,20 @@ void RecordWrite(ClipboardFormatMetric metric) {
   base::UmaHistogramEnumeration("Clipboard.Write", metric);
 }
 
+#if BUILDFLAG(IS_CHROMEOS)
+void RecordTimeIntervalBetweenCommitAndRead(const ui::ClipboardData* data) {
+  if (!data)
+    return;
+
+  absl::optional<base::Time> commit_time = data->commit_time();
+  if (!commit_time.has_value())
+    return;
+
+  base::UmaHistogramCustomTimes("Clipboard.TimeIntervalBetweenCommitAndRead",
+                                base::Time::Now() - commit_time.value(),
+                                /*min=*/base::Milliseconds(1),
+                                /*max=*/base::Hours(12), /*buckets=*/100);
+}
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
 }  // namespace ui

ui/base/clipboard/clipboard_metrics.h

@@ -5,8 +5,14 @@
 #ifndef UI_BASE_CLIPBOARD_CLIPBOARD_METRICS_H_
 #define UI_BASE_CLIPBOARD_CLIPBOARD_METRICS_H_
 
+#include "build/build_config.h"
+
 namespace ui {
 
+#if BUILDFLAG(IS_CHROMEOS)
+class ClipboardData;
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
 // Used to log formats read/written from/to the platform clipboard.
 //
 // This enum's values are persisted to logs. Do not reuse or renumber values.
@@ -28,6 +34,12 @@ enum class ClipboardFormatMetric {
 void RecordRead(ClipboardFormatMetric metric);
 void RecordWrite(ClipboardFormatMetric metric);
 
+#if BUILDFLAG(IS_CHROMEOS)
+// Records the time interval between when the specified |data| was committed to
+// the clipboard and when it was read. Read time is assumed to be now.
+void RecordTimeIntervalBetweenCommitAndRead(const ui::ClipboardData* data);
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
 }  // namespace ui
 
 #endif  // UI_BASE_CLIPBOARD_CLIPBOARD_METRICS_H_

ui/base/clipboard/clipboard_non_backed.cc

@@ -355,6 +355,9 @@ class ClipboardDataBuilder {
       ClipboardInternal* clipboard,
       std::unique_ptr<DataTransferEndpoint> data_src) {
     ClipboardData* data = GetCurrentData();
+#if BUILDFLAG(IS_CHROMEOS)
+    data->set_commit_time(base::Time::Now());
+#endif  // BUILDFLAG(IS_CHROMEOS)
     data->set_source(std::move(data_src));
     clipboard->WriteData(TakeCurrentData());
   }
@@ -587,6 +590,10 @@ void ClipboardNonBacked::ReadText(ClipboardBuffer buffer,
   if (!clipboard_internal_->IsReadAllowed(data_dst))
     return;
 
+#if BUILDFLAG(IS_CHROMEOS)
+  RecordTimeIntervalBetweenCommitAndRead(clipboard_internal_->GetData());
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
   RecordRead(ClipboardFormatMetric::kText);
   clipboard_internal_->ReadText(result);
 
@@ -603,6 +610,10 @@ void ClipboardNonBacked::ReadAsciiText(ClipboardBuffer buffer,
   if (!clipboard_internal_->IsReadAllowed(data_dst))
     return;
 
+#if BUILDFLAG(IS_CHROMEOS)
+  RecordTimeIntervalBetweenCommitAndRead(clipboard_internal_->GetData());
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
   RecordRead(ClipboardFormatMetric::kText);
   clipboard_internal_->ReadAsciiText(result);
 
@@ -622,6 +633,10 @@ void ClipboardNonBacked::ReadHTML(ClipboardBuffer buffer,
   if (!clipboard_internal_->IsReadAllowed(data_dst))
     return;
 
+#if BUILDFLAG(IS_CHROMEOS)
+  RecordTimeIntervalBetweenCommitAndRead(clipboard_internal_->GetData());
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
   RecordRead(ClipboardFormatMetric::kHtml);
   clipboard_internal_->ReadHTML(markup, src_url, fragment_start, fragment_end);
 
@@ -638,8 +653,16 @@ void ClipboardNonBacked::ReadSvg(ClipboardBuffer buffer,
   if (!clipboard_internal_->IsReadAllowed(data_dst))
     return;
 
+#if BUILDFLAG(IS_CHROMEOS)
+  RecordTimeIntervalBetweenCommitAndRead(clipboard_internal_->GetData());
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
   RecordRead(ClipboardFormatMetric::kSvg);
   clipboard_internal_->ReadSvg(result);
+
+#if BUILDFLAG(IS_CHROMEOS_ASH)
+  ClipboardMonitor::GetInstance()->NotifyClipboardDataRead();
+#endif
 }
 
 void ClipboardNonBacked::ReadRTF(ClipboardBuffer buffer,
@@ -650,6 +673,10 @@ void ClipboardNonBacked::ReadRTF(ClipboardBuffer buffer,
   if (!clipboard_internal_->IsReadAllowed(data_dst))
     return;
 
+#if BUILDFLAG(IS_CHROMEOS)
+  RecordTimeIntervalBetweenCommitAndRead(clipboard_internal_->GetData());
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
   RecordRead(ClipboardFormatMetric::kRtf);
   clipboard_internal_->ReadRTF(result);
 
@@ -668,6 +695,10 @@ void ClipboardNonBacked::ReadPng(ClipboardBuffer buffer,
     return;
   }
 
+#if BUILDFLAG(IS_CHROMEOS)
+  RecordTimeIntervalBetweenCommitAndRead(clipboard_internal_->GetData());
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
   RecordRead(ClipboardFormatMetric::kPng);
   clipboard_internal_->ReadPng(std::move(callback));
 
@@ -685,6 +716,10 @@ void ClipboardNonBacked::ReadCustomData(ClipboardBuffer buffer,
   if (!clipboard_internal_->IsReadAllowed(data_dst))
     return;
 
+#if BUILDFLAG(IS_CHROMEOS)
+  RecordTimeIntervalBetweenCommitAndRead(clipboard_internal_->GetData());
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
   RecordRead(ClipboardFormatMetric::kCustomData);
   clipboard_internal_->ReadCustomData(type, result);
 
@@ -702,6 +737,10 @@ void ClipboardNonBacked::ReadFilenames(
   if (!clipboard_internal_->IsReadAllowed(data_dst))
     return;
 
+#if BUILDFLAG(IS_CHROMEOS)
+  RecordTimeIntervalBetweenCommitAndRead(clipboard_internal_->GetData());
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
   RecordRead(ClipboardFormatMetric::kFilenames);
   *result = clipboard_internal_->ReadFilenames();
 
@@ -718,6 +757,10 @@ void ClipboardNonBacked::ReadBookmark(const DataTransferEndpoint* data_dst,
   if (!clipboard_internal_->IsReadAllowed(data_dst))
     return;
 
+#if BUILDFLAG(IS_CHROMEOS)
+  RecordTimeIntervalBetweenCommitAndRead(clipboard_internal_->GetData());
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
   RecordRead(ClipboardFormatMetric::kBookmark);
   clipboard_internal_->ReadBookmark(title, url);
 
@@ -734,6 +777,10 @@ void ClipboardNonBacked::ReadData(const ClipboardFormatType& format,
   if (!clipboard_internal_->IsReadAllowed(data_dst))
     return;
 
+#if BUILDFLAG(IS_CHROMEOS)
+  RecordTimeIntervalBetweenCommitAndRead(clipboard_internal_->GetData());
+#endif  // BUILDFLAG(IS_CHROMEOS)
+
   RecordRead(ClipboardFormatMetric::kData);
   clipboard_internal_->ReadData(format.GetName(), result);
 

ui/base/clipboard/clipboard_non_backed.h

@@ -51,11 +51,13 @@ class COMPONENT_EXPORT(UI_BASE_CLIPBOARD) ClipboardNonBacked
 
  private:
   friend class Clipboard;
-  friend class ClipboardNonBackedTest;
+  friend class ClipboardNonBackedTestBase;
   FRIEND_TEST_ALL_PREFIXES(ClipboardNonBackedTest, TextURIList);
   FRIEND_TEST_ALL_PREFIXES(ClipboardNonBackedTest, ImageEncoding);
   FRIEND_TEST_ALL_PREFIXES(ClipboardNonBackedTest, EncodeImageOnce);
   FRIEND_TEST_ALL_PREFIXES(ClipboardNonBackedTest, EncodeMultipleImages);
+  FRIEND_TEST_ALL_PREFIXES(ClipboardNonBackedMockTimeTest,
+                           RecordsTimeIntervalBetweenCommitAndRead);
   ClipboardNonBacked();
   ~ClipboardNonBacked() override;