Bug 879113 part 1/2, favicon errorhandling-Start screen should handle error cases when missing favicons, thumbnails gracefully.r=mbrubeck

browser/metro/base/content/TopSites.js

@@ -293,13 +293,15 @@ TopSitesView.prototype = {
       aTileNode.iconSrc = iconURLfromSiteURL.spec;
       let faviconURL = (PlacesUtils.favicons.getFaviconLinkForIcon(iconURLfromSiteURL)).spec;
       let xpFaviconURI = Util.makeURI(faviconURL.replace("moz-anno:favicon:",""));
-      ColorUtils.getForegroundAndBackgroundIconColors(xpFaviconURI, function(foreground, background) {
-        aTileNode.style.color = foreground; //color text
+      let successAction = function(foreground, background) {
+	      aTileNode.style.color = foreground; //color text
         aTileNode.setAttribute("customColor", background);
         if (aTileNode.refresh) {
           aTileNode.refresh();
         }
-      });
+      };
+      let failureAction = function() {};
+      ColorUtils.getForegroundAndBackgroundIconColors(xpFaviconURI, successAction, failureAction);
     });
 
     if (this._useThumbs) {

browser/metro/base/content/bookmarks.js

@@ -234,13 +234,15 @@ BookmarksView.prototype = {
     if (!aIconUri) {
       return;
     }
-    ColorUtils.getForegroundAndBackgroundIconColors(aIconUri, function(foregroundColor, backgroundColor) {
+    let successAction = function(foregroundColor, backgroundColor) {
       aItem.style.color = foregroundColor; //color text
       aItem.setAttribute("customColor", backgroundColor); //set background
       if (aItem.refresh) {
         aItem.refresh();
       }
-    });
+    };
+    let failureAction = function() {};
+    ColorUtils.getForegroundAndBackgroundIconColors(aIconUri, successAction, failureAction);
   },
 
   _sendNeedsRefresh: function bv__sendNeedsRefresh(){

browser/metro/modules/colorUtils.jsm

@@ -14,18 +14,20 @@ let ColorUtils = {
    *  & background color as is desired) The first argument to the callback is
    * the foreground/contrast color, the second is the background/primary/dominant one
    */
-  getForegroundAndBackgroundIconColors: function getForegroundAndBackgroundIconColors(aIconURI, aSuccessCallback) {
+  getForegroundAndBackgroundIconColors: function getForegroundAndBackgroundIconColors(aIconURI, aSuccessCallback, aErrorCallback) {
     if (!aIconURI) {
       return;
     }
-
     let that = this;
     let wrappedIcon = aIconURI;
     ColorAnalyzer.findRepresentativeColor(wrappedIcon, function (success, color) {
-      let foregroundColor = that.bestTextColorForContrast(color);
-      let backgroundColor = that.convertDecimalToRgbColor(color);
-      // let the caller do whatever it is they need through the callback
-      aSuccessCallback(foregroundColor, backgroundColor);
+      if (!success) {
+        aErrorCallback();
+      } else {
+        let foregroundColor = that.bestTextColorForContrast(color);
+        let backgroundColor = that.convertDecimalToRgbColor(color);
+        aSuccessCallback(foregroundColor, backgroundColor);
+      }
     }, this);
   },
   /** returns the best color for text readability on top of aColor