Add support to process favicons from Web Manifests

components/favicon/core/favicon_handler.h

Index: components/favicon/core/favicon_handler.h
diff --git a/components/favicon/core/favicon_handler.h b/components/favicon/core/favicon_handler.h
index 9e6e22b9f97126bc1762aa49db194d4225a8f635..e2a904b11e146b4811cef386955957c7f6cef04e 100644
--- a/components/favicon/core/favicon_handler.h
+++ b/components/favicon/core/favicon_handler.h
@@ -13,6 +13,7 @@
 #include "base/cancelable_callback.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
+#include "base/optional.h"
 #include "base/task/cancelable_task_tracker.h"
 #include "components/favicon/core/favicon_driver_observer.h"
 #include "components/favicon/core/favicon_url.h"
@@ -86,6 +87,10 @@ class FaviconHandler {
         const std::vector<gfx::Size>& original_bitmap_sizes)>
         ImageDownloadCallback;
 
+    typedef base::Callback<void(
+        const std::vector<favicon::FaviconURL>& favicons)>
+        ManifestDownloadCallback;
+
     // Starts the download for the given favicon. When finished, the callback
     // is called with the results. Returns the unique id of the download
     // request, which will also be passed to the callback. In case of error, 0
@@ -98,6 +103,10 @@ class FaviconHandler {
                               int max_image_size,
                               ImageDownloadCallback callback) = 0;
 
+    // Downloads a WebManifest and returns the favicons listed there.
+    virtual void DownloadManifest(const GURL& url,
+                                  ManifestDownloadCallback callback) = 0;
+
     // Returns whether the user is operating in an off-the-record context.
     virtual bool IsOffTheRecord() = 0;
 
@@ -124,10 +133,11 @@ class FaviconHandler {
   // Initiates loading the favicon for the specified url.
   void FetchFavicon(const GURL& url);
 
-  // Message Handler.  Must be public, because also called from
-  // PrerenderContents. Collects the |image_urls| list.
-  void OnUpdateFaviconURL(const GURL& page_url,
-                          const std::vector<favicon::FaviconURL>& candidates);
+  // Collects the candidate favicons as listed in the HTML head, as well as
+  // the WebManifest URL if available.
+  void OnUpdateCandidates(const GURL& page_url,
+                          const std::vector<favicon::FaviconURL>& candidates,
+                          const base::Optional<GURL>& manifest_url);
 
   // For testing.
   const std::vector<GURL> GetIconURLs() const;
@@ -174,6 +184,11 @@ class FaviconHandler {
   static int GetIconTypesFromHandlerType(
       FaviconDriverObserver::NotificationIconType handler_type);
 
+  // Called a list of favicon candidates to be processed is available, which can
+  // be either icon URLs listed in the HTML head instead or, if a Web Manifest
+  // was provided, the list of icons there.
+  void OnGotFinalIconURLCandidates(const std::vector<FaviconURL>& candidates);
+
   // Called when the history request for favicon data mapped to |url_| has
   // completed and the renderer has told us the icon URLs used by |url_|
   void OnGotInitialHistoryDataAndIconURLCandidates();
@@ -182,6 +197,10 @@ class FaviconHandler {
   void OnFaviconDataForInitialURLFromFaviconService(const std::vector<
       favicon_base::FaviconRawBitmapResult>& favicon_bitmap_results);
 
+  void OnFaviconDataForManifestURLFromFaviconService(
+      const std::vector<favicon_base::FaviconRawBitmapResult>&
+          favicon_bitmap_results);
+
   // If the favicon currently mapped to |url_| has expired, downloads the
   // current candidate favicon from the renderer. Otherwise requests data for
   // the current favicon from history. If data is requested from history,
@@ -265,9 +284,13 @@ class FaviconHandler {
   // |image_urls_| one by one.
   bool redownload_icons_;
 
+  // Requests to the renderer to download a manifest.
+  base::CancelableCallback<Delegate::ManifestDownloadCallback::RunType>
+      manifest_download_request_;
+
   // Requests to the renderer to download favicons.
   base::CancelableCallback<Delegate::ImageDownloadCallback::RunType>
-      download_request_;
+      image_download_request_;
 
   // The combination of the supported icon types.
   const int icon_types_;
@@ -275,6 +298,9 @@ class FaviconHandler {
   // Whether the largest icon should be downloaded.
   const bool download_largest_icon_;
 
+  // The manifest URL from the renderer.
+  base::Optional<GURL> manifest_url_;
+
   // The prioritized favicon candidates from the page back from the renderer.
   std::vector<FaviconCandidate> candidates_;