Remove ChromeBrowserProvider::GetFaviconForURL().

ios/public/provider/chrome/browser/chrome_browser_provider.mm

Index: ios/public/provider/chrome/browser/chrome_browser_provider.mm
diff --git a/ios/public/provider/chrome/browser/chrome_browser_provider.mm b/ios/public/provider/chrome/browser/chrome_browser_provider.mm
index dab8adfe483ba64de2728fe641128cf64e94c78d..f900bebc4c94269663abe66ccd17e290a6d6b04d 100644
--- a/ios/public/provider/chrome/browser/chrome_browser_provider.mm
+++ b/ios/public/provider/chrome/browser/chrome_browser_provider.mm
@@ -66,12 +66,6 @@ std::string ChromeBrowserProvider::GetRiskData() {
   return std::string();
 }
 
-void ChromeBrowserProvider::GetFaviconForURL(
-    ios::ChromeBrowserState* browser_state,
-    const GURL& page_url,
-    const std::vector<int>& desired_sizes_in_pixel,
-    const favicon_base::FaviconResultsCallback& callback) const {}
-
 UITextField<TextFieldStyling>* ChromeBrowserProvider::CreateStyledTextField(
     CGRect frame) const {
   return nil;