Add metrics for quantity and type of Favicon candidates

components/favicon/content/content_favicon_driver_unittest.cc

Index: components/favicon/content/content_favicon_driver_unittest.cc
diff --git a/components/favicon/content/content_favicon_driver_unittest.cc b/components/favicon/content/content_favicon_driver_unittest.cc
index d1ede99adfffb8888b2b18cecbb4c564245131ae..73769c5f2f222429a58d1a09df570d5584f7127b 100644
--- a/components/favicon/content/content_favicon_driver_unittest.cc
+++ b/components/favicon/content/content_favicon_driver_unittest.cc
@@ -9,6 +9,7 @@
 
 #include "base/macros.h"
 #include "base/run_loop.h"
+#include "base/test/histogram_tester.h"
 #include "components/favicon/core/favicon_client.h"
 #include "components/favicon/core/favicon_handler.h"
 #include "components/favicon/core/test/mock_favicon_service.h"
@@ -24,6 +25,7 @@
 namespace favicon {
 namespace {
 
+using testing::ElementsAre;
 using testing::Return;
 using testing::_;
 
@@ -135,9 +137,9 @@ TEST_F(ContentFaviconDriverTest, FaviconUpdateNoLastCommittedEntry) {
   ASSERT_EQ(nullptr, web_contents()->GetController().GetLastCommittedEntry());
 
   std::vector<content::FaviconURL> favicon_urls;
-  favicon_urls.push_back(content::FaviconURL(
-      GURL("http://www.google.ca/favicon.ico"), content::FaviconURL::FAVICON,
-      std::vector<gfx::Size>()));
+  favicon_urls.push_back(
+      content::FaviconURL(GURL("http://www.google.ca/favicon.ico"),
+                          content::FaviconURL::FAVICON, kEmptyIconSizes));
   favicon::ContentFaviconDriver* driver =
       favicon::ContentFaviconDriver::FromWebContents(web_contents());
   static_cast<content::WebContentsObserver*>(driver)
@@ -147,5 +149,49 @@ TEST_F(ContentFaviconDriverTest, FaviconUpdateNoLastCommittedEntry) {
   EXPECT_TRUE(driver->favicon_urls().empty());
 }
 
+TEST_F(ContentFaviconDriverTest, RecordsHistorgramsForCandidates) {
+  const std::vector<gfx::Size> kSizes16x16and32x32({{16, 16}, {32, 32}});
+  base::HistogramTester tester;
+  content::WebContentsObserver* driver_as_observer =
+      ContentFaviconDriver::FromWebContents(web_contents());
+
+  // Navigation to a page updating one icon.
+  NavigateAndCommit(GURL("http://www.youtube.com"));
+  driver_as_observer->DidUpdateFaviconURL(
+      {content::FaviconURL(GURL("http://www.youtube.com/favicon.ico"),
+                           content::FaviconURL::FAVICON, kSizes16x16and32x32)});
+
+  EXPECT_THAT(tester.GetAllSamples("Favicons.CandidatesCount"),
+              ElementsAre(base::Bucket(/*min=*/1, /*count=*/1)));
+  EXPECT_THAT(tester.GetAllSamples("Favicons.CandidatesWithDefinedSizesCount"),
+              ElementsAre(base::Bucket(/*min=*/1, /*count=*/1)));
+  EXPECT_THAT(tester.GetAllSamples("Favicons.CandidatesWithTouchIconsCount"),
+              ElementsAre(base::Bucket(/*min=*/0, /*count=*/1)));
+
+  std::vector<content::FaviconURL> favicon_urls = {
+      content::FaviconURL(GURL("http://www.google.ca/favicon.ico"),
+                          content::FaviconURL::FAVICON, kSizes16x16and32x32),
+      content::FaviconURL(GURL("http://www.google.ca/precomposed_icon.png"),
+                          content::FaviconURL::TOUCH_PRECOMPOSED_ICON,
+                          kEmptyIconSizes),
+      content::FaviconURL(GURL("http://www.google.ca/touch_icon.png"),
+                          content::FaviconURL::TOUCH_ICON, kEmptyIconSizes)};
+
+  // Double navigation to a page with 3 different icons.
+  NavigateAndCommit(GURL("http://www.google.ca"));
+  driver_as_observer->DidUpdateFaviconURL(favicon_urls);
+  NavigateAndCommit(GURL("http://www.google.ca"));
+  driver_as_observer->DidUpdateFaviconURL(favicon_urls);
+
+  EXPECT_THAT(tester.GetAllSamples("Favicons.CandidatesCount"),
+              ElementsAre(base::Bucket(/*min=*/1, /*count=*/1),
+                          base::Bucket(/*min=*/3, /*count=*/2)));
+  EXPECT_THAT(tester.GetAllSamples("Favicons.CandidatesWithDefinedSizesCount"),
+              ElementsAre(base::Bucket(/*min=*/1, /*count=*/3)));
+  EXPECT_THAT(tester.GetAllSamples("Favicons.CandidatesWithTouchIconsCount"),
+              ElementsAre(base::Bucket(/*min=*/0, /*count=*/1),
+                          base::Bucket(/*min=*/2, /*count=*/2)));
+}
+
 }  // namespace
 }  // namespace favicon