Fixed minor bug with Search.DefaultSearchChangeOrigin histogram

chrome/browser/search_engines/template_url_service_unittest.cc

Index: chrome/browser/search_engines/template_url_service_unittest.cc
diff --git a/chrome/browser/search_engines/template_url_service_unittest.cc b/chrome/browser/search_engines/template_url_service_unittest.cc
index c3b8de661f0c6b8c009edbf0d440e4c34cd821b0..9ec307fc0510367687fe267ac12591fe665dadae 100644
--- a/chrome/browser/search_engines/template_url_service_unittest.cc
+++ b/chrome/browser/search_engines/template_url_service_unittest.cc
@@ -20,6 +20,7 @@
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/task/cancelable_task_tracker.h"
+#include "base/test/histogram_tester.h"
 #include "base/test/simple_test_clock.h"
 #include "base/threading/thread.h"
 #include "base/time/time.h"
@@ -1944,3 +1945,22 @@ TEST_F(TemplateURLServiceTest, LastModifiedTimeUpdate) {
   EXPECT_NE(original_last_modified, reloaded_last_modified);
   EXPECT_EQ(update_last_modified, reloaded_last_modified);
 }
+
+// Tests checks that Search.DefaultSearchChangeOrigin histogram is correctly
+// emitted when TemplateURLService is not yet loaded.

[Peter Kasting, 2017/04/14 08:02:00]

Another way of testing would be to verify that
TemplateURLService::dsp_change_callback_ is run in this case.  This is probably
more important to get right than the histogram, though testing it might be
annoying.

+TEST_F(TemplateURLServiceTest, ChangeDefaultEngineBeforeLoad) {
+  TemplateURL* search_engine1 = model()->Add(
+      base::MakeUnique<TemplateURL>(*GenerateDummyTemplateURLData("keyword1")));
+  DCHECK(search_engine1);
+  TemplateURL* search_engine2 = model()->Add(
+      base::MakeUnique<TemplateURL>(*GenerateDummyTemplateURLData("keyword2")));
+  DCHECK(search_engine2);
+
+  base::HistogramTester histogram_tester;
+  model()->SetUserSelectedDefaultSearchProvider(search_engine1);
+  histogram_tester.ExpectTotalCount("Search.DefaultSearchChangeOrigin", 1);
+  model()->SetUserSelectedDefaultSearchProvider(search_engine1);
+  histogram_tester.ExpectTotalCount("Search.DefaultSearchChangeOrigin", 1);
+  model()->SetUserSelectedDefaultSearchProvider(search_engine2);
+  histogram_tester.ExpectTotalCount("Search.DefaultSearchChangeOrigin", 2);
+}