Record time spent on browsing data removal.

I added task_started time to RemovalTask structure, this was dropped
when this class was ported from content.

Bug: 796231, 759229
Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
Change-Id: I19f44ef3a72685b1fbe398e2915b8fd842307541
Reviewed-on: https://chromium-review.googlesource.com/1164571Reviewed-by: Eugene But <eugenebut@chromium.org>
Commit-Queue: Mohammad Refaat <mrefaat@chromium.org>
Cr-Commit-Position: refs/heads/master@{#581704}

ios/chrome/browser/browsing_data/browsing_data_remover_impl.h

@@ -64,6 +64,7 @@ class BrowsingDataRemoverImpl : public BrowsingDataRemover {
     base::Time delete_end;
     BrowsingDataRemoveMask mask;
     base::OnceClosure callback;
+    base::Time task_started;
   };
 
   // Setter for |is_removing_|; DCHECKs that we can only start removing if we're

ios/chrome/browser/browsing_data/browsing_data_remover_impl.mm

@@ -276,7 +276,8 @@ void BrowsingDataRemoverImpl::Remove(browsing_data::TimePeriod time_period,
 void BrowsingDataRemoverImpl::RunNextTask() {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   DCHECK(!removal_queue_.empty());
-  const RemovalTask& removal_task = removal_queue_.front();
+  RemovalTask& removal_task = removal_queue_.front();
+  removal_task.task_started = base::Time::Now();
   RemoveImpl(removal_task.delete_begin, removal_task.delete_end,
              removal_task.mask);
 }
@@ -674,6 +675,22 @@ void BrowsingDataRemoverImpl::NotifyRemovalComplete() {
 
   {
     RemovalTask task = std::move(removal_queue_.front());
+    // Only log clear browsing data on regular browsing mode. In OTR mode, only
+    // few types of data are cleared and the rest is handled by deleting the
+    // browser state, so logging in these cases will render the histogram not
+    // useful.
+    if (!browser_state_->IsOffTheRecord()) {
+      base::TimeDelta delta = base::Time::Now() - task.task_started;
+      bool is_deletion_start_earliest = task.delete_begin.is_null();
+      bool is_deletion_end_now = task.delete_end.is_max();
+      if (is_deletion_start_earliest && is_deletion_end_now) {
+        UMA_HISTOGRAM_MEDIUM_TIMES(
+            "History.ClearBrowsingData.Duration.FullDeletion", delta);
+      } else {
+        UMA_HISTOGRAM_MEDIUM_TIMES(
+            "History.ClearBrowsingData.Duration.PartialDeletion", delta);
+      }
+    }
     removal_queue_.pop();
 
     // Schedule the task to be executed soon. This ensure that the IsRemoving()

ios/chrome/browser/browsing_data/browsing_data_remover_impl_unittest.mm

@@ -13,6 +13,7 @@
 #include "base/run_loop.h"
 #include "base/scoped_observer.h"
 #import "base/test/ios/wait_util.h"
+#include "base/test/metrics/histogram_tester.h"
 #include "components/open_from_clipboard/clipboard_recent_content.h"
 #include "components/open_from_clipboard/fake_clipboard_recent_content.h"
 #include "ios/chrome/browser/browser_state/test_chrome_browser_state.h"
@@ -26,6 +27,9 @@
 #error "This file requires ARC support."
 #endif
 
+using base::test::ios::WaitUntilConditionOrTimeout;
+using base::test::ios::kWaitForActionTimeout;
+
 namespace {
 
 // Flags passed when calling Remove(). Clear as much data as possible, avoiding
@@ -45,6 +49,11 @@ constexpr BrowsingDataRemoveMask kRemoveMask =
     BrowsingDataRemoveMask::REMOVE_VISITED_LINKS |
     BrowsingDataRemoveMask::REMOVE_LAST_USER_ACCOUNT;
 
+const char kFullDeletionHistogram[] =
+    "History.ClearBrowsingData.Duration.FullDeletion";
+const char kPartialDeletionHistogram[] =
+    "History.ClearBrowsingData.Duration.PartialDeletion";
+
 // Observer used to validate that BrowsingDataRemoverImpl notifies its
 // observers.
 class TestBrowsingDataRemoverObserver : public BrowsingDataRemoverObserver {
@@ -114,12 +123,11 @@ TEST_F(BrowsingDataRemoverImplTest, InvokesObservers) {
                                 kRemoveMask, base::DoNothing());
 
   TestBrowsingDataRemoverObserver* observer_ptr = &observer;
-  EXPECT_TRUE(base::test::ios::WaitUntilConditionOrTimeout(
-      base::test::ios::kWaitForActionTimeout, ^{
-        // Spin the RunLoop as WaitUntilConditionOrTimeout doesn't.
-        base::RunLoop().RunUntilIdle();
-        return observer_ptr->last_remove_mask() == kRemoveMask;
-      }));
+  EXPECT_TRUE(WaitUntilConditionOrTimeout(kWaitForActionTimeout, ^{
+    // Spin the RunLoop as WaitUntilConditionOrTimeout doesn't.
+    base::RunLoop().RunUntilIdle();
+    return observer_ptr->last_remove_mask() == kRemoveMask;
+  }));
 }
 
 // Tests that BrowsingDataRemoverImpl::Remove() can be called multiple times.
@@ -134,12 +142,55 @@ TEST_F(BrowsingDataRemoverImplTest, SerializeRemovals) {
                                   --remaining_calls;
                                 }));
 
-  EXPECT_TRUE(base::test::ios::WaitUntilConditionOrTimeout(
-      base::test::ios::kWaitForActionTimeout, ^{
-        // Spin the RunLoop as WaitUntilConditionOrTimeout doesn't.
-        base::RunLoop().RunUntilIdle();
-        return remaining_calls == 0;
-      }));
+  EXPECT_TRUE(WaitUntilConditionOrTimeout(kWaitForActionTimeout, ^{
+    // Spin the RunLoop as WaitUntilConditionOrTimeout doesn't.
+    base::RunLoop().RunUntilIdle();
+    return remaining_calls == 0;
+  }));
+}
+
+// Tests that BrowsingDataRemoverImpl::Remove() Logs the duration to the correct
+// histogram for full deletion.
+TEST_F(BrowsingDataRemoverImplTest, LogDurationForFullDeletion) {
+  base::HistogramTester histogram_tester;
+  __block int remaining_calls = 1;
+  histogram_tester.ExpectTotalCount(kFullDeletionHistogram, 0);
+  histogram_tester.ExpectTotalCount(kPartialDeletionHistogram, 0);
+
+  browsing_data_remover_.Remove(browsing_data::TimePeriod::ALL_TIME,
+                                kRemoveMask, base::BindOnce(^{
+                                  --remaining_calls;
+                                }));
+  EXPECT_TRUE(WaitUntilConditionOrTimeout(kWaitForActionTimeout, ^{
+    // Spin the RunLoop as WaitUntilConditionOrTimeout doesn't.
+    base::RunLoop().RunUntilIdle();
+    return remaining_calls == 0;
+  }));
+
+  histogram_tester.ExpectTotalCount(kFullDeletionHistogram, 1);
+  histogram_tester.ExpectTotalCount(kPartialDeletionHistogram, 0);
+}
+
+// Tests that BrowsingDataRemoverImpl::Remove() Logs the duration to the correct
+// histogram for partial deletion.
+TEST_F(BrowsingDataRemoverImplTest, LogDurationForPartialDeletion) {
+  base::HistogramTester histogram_tester;
+  __block int remaining_calls = 1;
+  histogram_tester.ExpectTotalCount(kFullDeletionHistogram, 0);
+  histogram_tester.ExpectTotalCount(kPartialDeletionHistogram, 0);
+
+  browsing_data_remover_.Remove(browsing_data::TimePeriod::LAST_HOUR,
+                                kRemoveMask, base::BindOnce(^{
+                                  --remaining_calls;
+                                }));
+  EXPECT_TRUE(WaitUntilConditionOrTimeout(kWaitForActionTimeout, ^{
+    // Spin the RunLoop as WaitUntilConditionOrTimeout doesn't.
+    base::RunLoop().RunUntilIdle();
+    return remaining_calls == 0;
+  }));
+
+  histogram_tester.ExpectTotalCount(kFullDeletionHistogram, 0);
+  histogram_tester.ExpectTotalCount(kPartialDeletionHistogram, 1);
 }
 
 // Tests that BrowsingDataRemoverImpl::Remove() can finish performing its
@@ -154,10 +205,9 @@ TEST_F(BrowsingDataRemoverImplTest, PerformAfterBrowserStateDestruction) {
   // Simulate destruction of BrowserState.
   browsing_data_remover_.Shutdown();
 
-  EXPECT_TRUE(base::test::ios::WaitUntilConditionOrTimeout(
-      base::test::ios::kWaitForActionTimeout, ^{
-        // Spin the RunLoop as WaitUntilConditionOrTimeout doesn't.
-        base::RunLoop().RunUntilIdle();
-        return remaining_calls == 0;
-      }));
+  EXPECT_TRUE(WaitUntilConditionOrTimeout(kWaitForActionTimeout, ^{
+    // Spin the RunLoop as WaitUntilConditionOrTimeout doesn't.
+    base::RunLoop().RunUntilIdle();
+    return remaining_calls == 0;
+  }));
 }