Add picker view for Web Share Target.

chrome/browser/webshare/share_service_impl.h

Index: chrome/browser/webshare/share_service_impl.h
diff --git a/chrome/browser/webshare/share_service_impl.h b/chrome/browser/webshare/share_service_impl.h
index 8bd381f7c97df971ee70604a7804d264e6aad7ef..d79b7e27bea2375eec4ca9bd4eac3b5c276889d2 100644
--- a/chrome/browser/webshare/share_service_impl.h
+++ b/chrome/browser/webshare/share_service_impl.h
@@ -48,6 +48,12 @@ class ShareServiceImpl : public blink::mojom::ShareService {
                                   const GURL& share_url,
                                   std::string* url_template_filled);
 
+  void OnPickerClosed(const std::string& title,
+                      const std::string& text,
+                      const GURL& share_url,
+                      const ShareCallback& callback,
+                      bool picked);
+
   DISALLOW_COPY_AND_ASSIGN(ShareServiceImpl);
 };