[Favicon] Add new fallback icon rendering flow.

chrome/browser/favicon/favicon_service.cc

Index: chrome/browser/favicon/favicon_service.cc
diff --git a/chrome/browser/favicon/favicon_service.cc b/chrome/browser/favicon/favicon_service.cc
index 064151e925a10491667a4d449234b26602522807..5e33fcb5714ed6c5b0c6d56f8733fd83d43ae7ef 100644
--- a/chrome/browser/favicon/favicon_service.cc
+++ b/chrome/browser/favicon/favicon_service.cc
@@ -14,7 +14,7 @@
 #include "chrome/browser/ui/webui/chrome_web_ui_controller_factory.h"
 #include "chrome/common/importer/imported_favicon_usage.h"
 #include "chrome/common/url_constants.h"
-#include "components/favicon_base/favicon_types.h"
+#include "components/favicon_base/fallback_icon_service.h"
 #include "components/favicon_base/favicon_util.h"
 #include "components/favicon_base/select_favicon_frames.h"
 #include "extensions/common/constants.h"
@@ -22,11 +22,14 @@
 #include "ui/gfx/codec/png_codec.h"
 #include "ui/gfx/favicon_size.h"
 #include "ui/gfx/image/image_skia.h"
+#include "url/gurl.h"
 
 using base::Bind;
 
 namespace {
 
+const int kMaxFallbackFaviconSize = 288;
+
 void CancelOrRunFaviconResultsCallback(
     const base::CancelableTaskTracker::IsCanceledCallback& is_canceled,
     const favicon_base::FaviconResultsCallback& callback,
@@ -81,6 +84,7 @@ FaviconService::FaviconService(Profile* profile, FaviconClient* favicon_client)
     : history_service_(HistoryServiceFactory::GetForProfile(
           profile,
           ServiceAccessType::EXPLICIT_ACCESS)),
+      fallback_icon_service_(new favicon_base::FallbackIconService()),
       profile_(profile),
       favicon_client_(favicon_client) {
 }
@@ -170,6 +174,29 @@ base::CancelableTaskTracker::TaskId FaviconService::GetFaviconImageForPageURL(
       tracker);
 }
 
+base::CancelableTaskTracker::TaskId FaviconService::GetRawFallbackFaviconImage(
+    const GURL& icon_url,
+    favicon_base::IconType icon_type,
+    int desired_size_in_pixel,
+    const favicon_base::FallbackIconSpecs& specs,
+    const favicon_base::FaviconRawBitmapCallback& callback,
+    base::CancelableTaskTracker* tracker) {
+  int size_to_use = desired_size_in_pixel;
+  if (desired_size_in_pixel == 0 ||
+      desired_size_in_pixel > kMaxFallbackFaviconSize) {
+    size_to_use = kMaxFallbackFaviconSize;
+  }
+
+  favicon_base::FaviconResultsCallback callback_runner =
+      Bind(&FaviconService::RunFaviconRawBitmapCallbackWithBitmapResults,
+           base::Unretained(this),
+           callback,
+           size_to_use);
+
+  return fallback_icon_service_->GetFallbackIcon(
+      icon_url, size_to_use, specs, callback_runner, tracker);
+}
+
 base::CancelableTaskTracker::TaskId FaviconService::GetRawFaviconForPageURL(
     const GURL& page_url,
     int icon_types,