Avoid sending notifications when the bitmap data in history has not changed

chrome/browser/history/history_backend_unittest.cc

 // Copyright (c) 2012 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 <algorithm>
 #include <set>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
@@ skipping 1774 matching lines @@
   FaviconSizes favicon_sizes;
   EXPECT_TRUE(backend_->thumbnail_db_->GetFaviconHeader(
       icon_mappings[0].icon_id, NULL, NULL, &favicon_sizes));
   EXPECT_EQ(GetSizesSmallAndLarge(), favicon_sizes);
 
   FaviconBitmap favicon_bitmap;
   EXPECT_TRUE(GetOnlyFaviconBitmap(icon_mappings[0].icon_id, &favicon_bitmap));
   EXPECT_TRUE(BitmapDataEqual('a', favicon_bitmap.bitmap_data));
   EXPECT_EQ(kSmallSize, favicon_bitmap.pixel_size);
 
-  // 1) Merge favicon of the same size.
+  EXPECT_EQ(1, num_broadcasted_notifications());
+
+  // 1) Merge identical favicon bitmap.
   std::vector<unsigned char> data;
-  data.push_back('b');
+  data.push_back('a');
   scoped_refptr<base::RefCountedBytes> bitmap_data(
       new base::RefCountedBytes(data));
   backend_->MergeFavicon(page_url, icon_url1, FAVICON, bitmap_data, kSmallSize);
 
+  // All the data should stay the same and no notifications should have been
+  // sent.
+  icon_mappings.clear();
+  EXPECT_TRUE(backend_->thumbnail_db_->GetIconMappingsForPageURL(page_url,
+      &icon_mappings));
+  EXPECT_EQ(1u, icon_mappings.size());
+  EXPECT_EQ(icon_url1, icon_mappings[0].icon_url);
+
+  favicon_sizes.clear();
+  EXPECT_TRUE(backend_->thumbnail_db_->GetFaviconHeader(
+      icon_mappings[0].icon_id, NULL, NULL, &favicon_sizes));
+  EXPECT_EQ(GetSizesSmallAndLarge(), favicon_sizes);
+
+  EXPECT_TRUE(GetOnlyFaviconBitmap(icon_mappings[0].icon_id, &favicon_bitmap));
+  EXPECT_TRUE(BitmapDataEqual('a', favicon_bitmap.bitmap_data));
+  EXPECT_EQ(kSmallSize, favicon_bitmap.pixel_size);
+
+  EXPECT_EQ(1, num_broadcasted_notifications());
+
+  // 2) Merge favicon bitmap of the same size.
+  data[0] = 'b';
+  bitmap_data = new base::RefCountedBytes(data);
+  backend_->MergeFavicon(page_url, icon_url1, FAVICON, bitmap_data, kSmallSize);
+
   // The small favicon bitmap at |icon_url1| should be overwritten and favicon
   // sizes should remain unchanged.
   icon_mappings.clear();
   EXPECT_TRUE(backend_->thumbnail_db_->GetIconMappingsForPageURL(page_url,
       &icon_mappings));
   EXPECT_EQ(1u, icon_mappings.size());
   EXPECT_EQ(icon_url1, icon_mappings[0].icon_url);
 
   favicon_sizes.clear();
   EXPECT_TRUE(backend_->thumbnail_db_->GetFaviconHeader(
       icon_mappings[0].icon_id, NULL, NULL, &favicon_sizes));
   EXPECT_EQ(GetSizesSmallAndLarge(), favicon_sizes);
 
   EXPECT_TRUE(GetOnlyFaviconBitmap(icon_mappings[0].icon_id, &favicon_bitmap));
   EXPECT_TRUE(BitmapDataEqual('b', favicon_bitmap.bitmap_data));
   EXPECT_EQ(kSmallSize, favicon_bitmap.pixel_size);
 
-  // 2) Merge favicon for the same icon URL, but a pixel size for which there is
+  // 3) Merge favicon for the same icon URL, but a pixel size for which there is
   // no favicon bitmap.
   data[0] = 'c';
   bitmap_data = new base::RefCountedBytes(data);
   backend_->MergeFavicon(page_url, icon_url1, FAVICON, bitmap_data, kTinySize);
 
   // A new favicon bitmap should be created and favicon sizes should be set to
   // the default.
   icon_mappings.clear();
   EXPECT_TRUE(backend_->thumbnail_db_->GetIconMappingsForPageURL(page_url,
       &icon_mappings));
   EXPECT_EQ(1u, icon_mappings.size());
   EXPECT_EQ(icon_url1, icon_mappings[0].icon_url);
 
   favicon_sizes.clear();
   EXPECT_TRUE(backend_->thumbnail_db_->GetFaviconHeader(
       icon_mappings[0].icon_id, NULL, NULL, &favicon_sizes));
   EXPECT_EQ(GetDefaultFaviconSizes(), favicon_sizes);
 
   std::vector<FaviconBitmap> favicon_bitmaps;
   EXPECT_TRUE(GetSortedFaviconBitmaps(icon_mappings[0].icon_id,
                                       &favicon_bitmaps));
   EXPECT_TRUE(BitmapDataEqual('c', favicon_bitmaps[0].bitmap_data));
   EXPECT_EQ(kTinySize, favicon_bitmaps[0].pixel_size);
   EXPECT_TRUE(BitmapDataEqual('b', favicon_bitmaps[1].bitmap_data));
   EXPECT_EQ(kSmallSize, favicon_bitmaps[1].pixel_size);
 
-  // 3) Merge favicon for an icon URL different from the icon URLs already
+  // 4) Merge favicon for an icon URL different from the icon URLs already
   // mapped to page URL.
   data[0] = 'd';
   bitmap_data = new base::RefCountedBytes(data);
   backend_->MergeFavicon(page_url, icon_url2, FAVICON, bitmap_data, kSmallSize);
 
   // The existing favicon bitmaps should be copied over to the newly created
   // favicon at |icon_url2|. |page_url| should solely be mapped to |icon_url2|.
   icon_mappings.clear();
   EXPECT_TRUE(backend_->thumbnail_db_->GetIconMappingsForPageURL(page_url,
       &icon_mappings));
@@ skipping 826 matching lines @@
             backend_->GetFirstRecordedTimeForTest());
 
   EXPECT_FALSE(backend_->GetURL(args[0].url, &row));
   EXPECT_TRUE(backend_->GetURL(args[1].url, &row));
   EXPECT_FALSE(backend_->GetURL(args[2].url, &row));
   EXPECT_TRUE(backend_->GetURL(args[3].url, &row));
   EXPECT_FALSE(backend_->GetURL(args[4].url, &row));
 }
 
 }  // namespace history