Use IOSImageDataFetcherWrapper in BrowserViewController

components/image_fetcher/image_data_fetcher.h

Index: components/image_fetcher/image_data_fetcher.h
diff --git a/components/image_fetcher/image_data_fetcher.h b/components/image_fetcher/image_data_fetcher.h
index 92c5a5cf0dc233d7c004adc58387f336115361bf..b2775ff829c7ff88d3e27004754282d554787a67 100644
--- a/components/image_fetcher/image_data_fetcher.h
+++ b/components/image_fetcher/image_data_fetcher.h
@@ -14,6 +14,7 @@
 #include "base/memory/ref_counted.h"
 #include "components/data_use_measurement/core/data_use_user_data.h"
 #include "net/url_request/url_fetcher_delegate.h"
+#include "net/url_request/url_request.h"
 #include "url/gurl.h"
 
 namespace net {
@@ -37,11 +38,19 @@ class ImageDataFetcher : public net::URLFetcherDelegate {
   // Sets a service name against which to track data usage.
   void SetDataUseServiceName(DataUseServiceName data_use_service_name);
 
+  // Helper to fetches images data without a referrer.

[Marc Treib, 2017/02/02 15:19:13]

s/fetches images/fetch image/

Though I might do the comments the other way around: Have the "main" comment
here, and then on the overload below, say just "Like above, but lets the caller
set a referrer". (Not a big deal either way)

[gambard, 2017/02/03 12:11:34]

Done.

+  void FetchImageData(const GURL& image_url,
+                      const ImageDataFetcherCallback& callback);
+
   // Fetches the raw image bytes from the given |image_url| and calls the given
   // |callback|. The callback is run even if fetching the URL fails. In case
   // of an error an empty string is passed to the callback.
+  // The |referrer| and |referrer_policy| will be passed on to the underlying
+  // URLFetcher.
   void FetchImageData(const GURL& image_url,
-                      const ImageDataFetcherCallback& callback);
+                      const ImageDataFetcherCallback& callback,
+                      const std::string& referrer,
+                      net::URLRequest::ReferrerPolicy referrer_policy);
 
  private:
   struct ImageDataFetcherRequest;