Favicon url is used only if it is valid

ios/web/web_state/ui/crw_web_controller.mm

Index: ios/web/web_state/ui/crw_web_controller.mm
diff --git a/ios/web/web_state/ui/crw_web_controller.mm b/ios/web/web_state/ui/crw_web_controller.mm
index ef9d4bd1dcc9b4acf23e91bbe6b490f279f3ff7c..a434d4a192cff28ef218ac6a78ef500153543b58 100644
--- a/ios/web/web_state/ui/crw_web_controller.mm
+++ b/ios/web/web_state/ui/crw_web_controller.mm
@@ -2563,8 +2563,10 @@ registerLoadRequestForURL:(const GURL&)requestURL
       icon_type = web::FaviconURL::TOUCH_ICON;
     else if (rel == "apple-touch-icon-precomposed")
       icon_type = web::FaviconURL::TOUCH_PRECOMPOSED_ICON;
-    urls.push_back(
-        web::FaviconURL(GURL(href), icon_type, std::vector<gfx::Size>()));
+    GURL url = GURL(href);

[Eugene But (OOO till 7-30), 2017/05/12 15:04:08]

WebContentsObserver also has DidUpdateFaviconURL. Does content throw away
invalid URLs as well? I think we should do the same thing as other platforms,
but also update WebStateObserver::FaviconUrlUpdated comments to explicitly say
whether or not the result will contain invalid URLs. 

[gambard, 2017/05/12 15:43:39]

There is a check if the URL is empty
https://cs.chromium.org/chromium/src/content/renderer/render_view_impl.cc?sq=...
So I guess there might be a check to see if it is valid?

+    if (url.is_valid()) {
+      urls.push_back(web::FaviconURL(url, icon_type, std::vector<gfx::Size>()));
+    }
   }
   if (!urls.empty())
     _webStateImpl->OnFaviconUrlUpdated(urls);