[ios] Snapshot for WebState

ios/web/public/test/fakes/test_web_state.mm

Index: ios/web/public/test/fakes/test_web_state.mm
diff --git a/ios/web/public/test/fakes/test_web_state.mm b/ios/web/public/test/fakes/test_web_state.mm
index 9c268874967e742a94a6ae680562f19ed78fccb5..787d4b879aeebf739600c8f3ed774f1ced7c5429 100644
--- a/ios/web/public/test/fakes/test_web_state.mm
+++ b/ios/web/public/test/fakes/test_web_state.mm
@@ -9,6 +9,7 @@
 #include "base/callback.h"
 #import "ios/web/public/web_state/ui/crw_content_view.h"
 #include "ios/web/public/web_state/web_state_observer.h"
+#include "ui/gfx/image/image.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
@@ -230,6 +231,11 @@ bool TestWebState::HasOpener() const {
   return false;
 }
 
+void TestWebState::TakeSnapshot(
+    const base::Callback<void(const gfx::Image& snapshot)>& callback) const {
+  callback.Run(gfx::Image());

[Eugene But (OOO till 7-30), 2017/06/21 22:11:28]

Should this be asynchronous call?

[edchin, 2017/06/22 07:01:07]

Done. Using SequencedTaskRunner.

+}
+
 base::WeakPtr<WebState> TestWebState::AsWeakPtr() {
   NOTREACHED();
   return base::WeakPtr<WebState>();