[Content suggestions] Add a function to the service API to fetch favicons

chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SuggestionsSource.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SuggestionsSource.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SuggestionsSource.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SuggestionsSource.java
index 073147059a8ed649918b63bee512cfe476f0b4c0..cfc78b9e24fa091e302e5b6fb709fb63b09d9b02 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SuggestionsSource.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SuggestionsSource.java
@@ -76,6 +76,20 @@ public interface SuggestionsSource {
     void fetchSuggestionImage(SnippetArticle suggestion, Callback<Bitmap> callback);
 
     /**
+     * Fetches the favicon for a content suggestion. A null Bitmap is returned if no good favicon is
+     * available. The callback is never called synchronously.
+     * @param suggestion The suggestion which the favicon should represent.
+     * @param minimumSizePx Minimal required size, if only a smaller favicon is available, a null
+     * Bitmap is returned.
+     * @param desiredSizePx If set to 0, it denotes that the favicon should be returned in its
+     * original size (as in favicon cache) without being resized. If not 0, it must be larger or
+     * equal to the minimum size and the favicon will be returned resized to this size.
+     * @param callback The callback that receives the favicon image.
+     */
+    void fetchSuggestionFavicon(SnippetArticle suggestion, int minimumSizePx, int desiredSizePx,
+            Callback<Bitmap> callback);
+
+    /**
      * Fetches new suggestions.
      * @param category the category to fetch new suggestions for.
      * @param displayedSuggestionIds ids of suggestions already known and that we want to keep.
@@ -101,4 +115,4 @@ public interface SuggestionsSource {
      * Sets the recipient for update events from the source.
      */
     void setObserver(Observer observer);
-}
+}