Disable Share extension item receiver if there is no app group.

ios/chrome/browser/share_extension/share_extension_item_receiver.mm

Index: ios/chrome/browser/share_extension/share_extension_item_receiver.mm
diff --git a/ios/chrome/browser/share_extension/share_extension_item_receiver.mm b/ios/chrome/browser/share_extension/share_extension_item_receiver.mm
index 677f1ec931b4f7eb492774ca48c33413b1bb5297..a63334068cb0ad2dd50b566448eaeb6493f4f3b6 100644
--- a/ios/chrome/browser/share_extension/share_extension_item_receiver.mm
+++ b/ios/chrome/browser/share_extension/share_extension_item_receiver.mm
@@ -98,13 +98,9 @@ void LogHistogramReceivedItem(ShareExtensionItemReceived type) {
   DCHECK(!_readingListModel);
   DCHECK(!_bookmarkModel);
 
-#if TARGET_IPHONE_SIMULATOR

[rohitrao (ping after 24h), 2016/12/19 09:40:33]

We're running egtests on devices as well, that's where I first noticed the
issue.  I'm not sure I've ever actually seen this crash on simulator.

Will this change cause any tests to fail, since we're effectively turning off
functionality?

Should we add the entitlement to egtests instead?

[sdefresne, 2016/12/20 01:03:38]

I think we should try to get the entitlements for egtests, but it needs some
work. For the moment, I think it is fine just turning this off.

   if (![self presentedItemURL]) {
     return;
   }
-#else
-  DCHECK([self presentedItemURL]);
-#endif
 
   _readingListModel = readingListModel;
   _bookmarkModel = bookmarkModel;