title: "setURLToShare" must be called for call-to-action to work
body: <p>Till yesterday I was able to execute following code to share on user's google+ profile but suddenly today it says in console log that <code>[GPPShareBuilderImpl getURL] |setURLToShare:| must be called for call-to-action to work</code>. 
  <br><br><strong>Code :</strong><br></p>
  
  <pre><code>[GPPShare sharedInstance].delegate = self;
  
  id&lt;GPPShareBuilder&gt; shareBuilder = [[GPPShare sharedInstance] shareDialog];
  
  // This line will manually fill out the title, description, and thumbnail of the
  // item you're sharing.
  [shareBuilder setTitle:@"AppName"
             description:@"App description."
            thumbnailURL:[NSURL URLWithString:@"https://www.example.com/image.png"]];
  
  /* This line passes the deepLinkID to our application
   if somebody opens the link on a supported mobile device */
  [shareBuilder setContentDeepLinkID:@"post"];
  
  // set the text of post. user can edit this before sharing.
  [shareBuilder setPrefillText:@"I just created a trip from XYZ app."];
  
  // This will create a call-to-action button with the specified label.
  // - URL specifies where people will go if they click the button on a platform
  // that doesn't support deep linking.
  // - deepLinkID specifies the deep-link identifier that is passed to your native
  // application on platforms that do support deep linking
  [shareBuilder setCallToActionButtonWithLabel:@"Install"
                                           URL:[NSURL URLWithString:@"http://www.example.com/"]
                                    deepLinkID:@"install"];
  
  [shareBuilder open];
  </code></pre>
  
  <p><br><br>According to <a href="https://developers.google.com/+/mobile/ios/share" rel="nofollow">Google+ documentation</a>(<code>Share without URL</code> section) I can use below method instead of <code>setURLToShare:</code>. And this method was working fine till yesterday.<br></p>
  
  <pre><code>[shareBuilder setTitle:@"title"
                   description:@"description";
                  thumbnailURL:@"url"];
  </code></pre>
  
  <p>I have not found anything on Google+ related to this. I tried deleting the app and installing again. Any idea what to do?</p>