Reading List: Mark entry read when opening external app.

ios/web/public/web_state/ui/crw_web_delegate.h

Index: ios/web/public/web_state/ui/crw_web_delegate.h
diff --git a/ios/web/public/web_state/ui/crw_web_delegate.h b/ios/web/public/web_state/ui/crw_web_delegate.h
index eb6a81c8835b33b9e82b98d89290321781126210..c237738283be18549959ba92490ba727ddd1ab06 100644
--- a/ios/web/public/web_state/ui/crw_web_delegate.h
+++ b/ios/web/public/web_state/ui/crw_web_delegate.h
@@ -26,6 +26,10 @@ class GURL;
 // TODO(crbug.com/674991): Remove this protocol.
 @protocol CRWWebDelegate<NSObject>
 
+// Current navigation triggered an external app so the loading will be
+// cancelled.
+- (void)currentNavigationWillContinueInExternalApp;

[Eugene But (OOO till 7-30), 2017/03/29 15:44:15]

We should really avoid adding new methods to CRWWebDelegate (we working on
removing this protocol). CRWWebDelegate already has 4 methods for launching
external apps, so can we reuse |openExternalURL:linkClicked:| instead of adding
a new one?

[Olivier, 2017/03/29 15:49:45]

|openExternalURL:linkClicked:| is called after [self stopLoading];in the web
controller.

So data on the current navigation is lost (and if the current page is native,
like an ntp, a navigation to chrome://newtab is synchronously triggered).

So to reuse |openExternalURL:linkClicked:|, we should either save and pass the
data of the previous navigation, or move the call to [self stopLoading]; after
the call to  |openExternalURL:linkClicked:|.

If you think one of these changes is safer, I can do it.

+
 // Called when an external app needs to be opened, it also passes |linkClicked|
 // to track if this call was a result of user action or not. Returns YES iff
 // |URL| is launched in an external app.