[LargeIconService] Report size of favicon for fallback style to UMA

components/favicon/core/large_icon_service_unittest.cc

 // Copyright 2015 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 "components/favicon/core/large_icon_service.h"
 
 #include <deque>
 #include <memory>
 
 #include "base/bind.h"
@@ skipping 381 matching lines @@
   GetLargeIconOrFallbackStyleAndWaitForCallback(GURL(kDummyUrl), 16, 0);
   EXPECT_EQ(gfx::Size(24, 24), *returned_bitmap_size_);
   EXPECT_EQ(nullptr, returned_fallback_style_);
 }
 
 TEST_P(LargeIconServiceGetterTest, FallbackSinceIconTooSmall) {
   InjectMockResult(GURL(kDummyUrl), CreateTestBitmapResult(16, 16, kTestColor));
   GetLargeIconOrFallbackStyleAndWaitForCallback(GURL(kDummyUrl), 24, 24);
   EXPECT_EQ(nullptr, returned_bitmap_size_);
   EXPECT_TRUE(HasBackgroundColor(*returned_fallback_style_, kTestColor));
+  histogram_tester_.ExpectUniqueSample("Favicons.LargeIconService.FallbackSize",
+                                       16, /*expected_count=*/1);
 }
 
 TEST_P(LargeIconServiceGetterTest, FallbackSinceIconNotSquare) {
   InjectMockResult(GURL(kDummyUrl), CreateTestBitmapResult(24, 32, kTestColor));
   GetLargeIconOrFallbackStyleAndWaitForCallback(GURL(kDummyUrl), 24, 24);
   EXPECT_EQ(nullptr, returned_bitmap_size_);
   EXPECT_TRUE(HasBackgroundColor(*returned_fallback_style_, kTestColor));
+  histogram_tester_.ExpectUniqueSample("Favicons.LargeIconService.FallbackSize",
+                                       24, /*expected_count=*/1);
 }
 
 TEST_P(LargeIconServiceGetterTest, FallbackSinceIconMissing) {
   InjectMockResult(GURL(kDummyUrl), favicon_base::FaviconRawBitmapResult());
   GetLargeIconOrFallbackStyleAndWaitForCallback(GURL(kDummyUrl), 24, 24);
   EXPECT_EQ(nullptr, returned_bitmap_size_);
   EXPECT_TRUE(returned_fallback_style_->is_default_background_color);
+  histogram_tester_.ExpectUniqueSample("Favicons.LargeIconService.FallbackSize",
+                                       0, /*expected_count=*/1);
 }
 
 TEST_P(LargeIconServiceGetterTest, FallbackSinceIconMissingNoScale) {
   InjectMockResult(GURL(kDummyUrl), favicon_base::FaviconRawBitmapResult());
   GetLargeIconOrFallbackStyleAndWaitForCallback(GURL(kDummyUrl), 24, 0);
   EXPECT_EQ(nullptr, returned_bitmap_size_);
   EXPECT_TRUE(returned_fallback_style_->is_default_background_color);
+  histogram_tester_.ExpectUniqueSample("Favicons.LargeIconService.FallbackSize",
+                                       0, /*expected_count=*/1);
 }
 
 // Oddball case where we demand a high resolution icon to scale down. Generates
 // fallback even though an icon with the final size is available.
 TEST_P(LargeIconServiceGetterTest, FallbackSinceTooPicky) {
   InjectMockResult(GURL(kDummyUrl), CreateTestBitmapResult(24, 24, kTestColor));
   GetLargeIconOrFallbackStyleAndWaitForCallback(GURL(kDummyUrl), 32, 24);
   EXPECT_EQ(nullptr, returned_bitmap_size_);
   EXPECT_TRUE(HasBackgroundColor(*returned_fallback_style_, kTestColor));
+  histogram_tester_.ExpectUniqueSample("Favicons.LargeIconService.FallbackSize",
+                                       24, /*expected_count=*/1);
 }
 
 // Every test will appear with suffix /0 (param false) and /1 (param true), e.g.
 //  LargeIconServiceGetterTest.FallbackSinceTooPicky/0: get image.
 //  LargeIconServiceGetterTest.FallbackSinceTooPicky/1: get raw bitmap.
 INSTANTIATE_TEST_CASE_P(,  // Empty instatiation name.
                         LargeIconServiceGetterTest,
                         ::testing::Values(false, true));
 
 }  // namespace
 }  // namespace favicon