Add public API for handling Javascript alerts and prompt.

ios/web/web_state/web_state_impl.h

Index: ios/web/web_state/web_state_impl.h
diff --git a/ios/web/web_state/web_state_impl.h b/ios/web/web_state/web_state_impl.h
index 776416c8e6baf81801535d5ca304b9a8be403ef4..d670e805ffbb1e3c10d4749b424039d2cc1a8d6f 100644
--- a/ios/web/web_state/web_state_impl.h
+++ b/ios/web/web_state/web_state_impl.h
@@ -20,7 +20,9 @@
 #include "ios/web/navigation/navigation_manager_delegate.h"
 #include "ios/web/navigation/navigation_manager_impl.h"
 #include "ios/web/net/request_tracker_impl.h"
+#include "ios/web/public/javascript_message_type.h"
 #include "ios/web/public/web_state/web_state.h"
+#include "net/base/auth.h"
 #include "url/gurl.h"
 
 @protocol CRWRequestTrackerDelegate;
@@ -267,6 +269,32 @@ class WebStateImpl : public WebState, public NavigationManagerDelegate {
   // Notifies the delegate that a context menu needs handling.
   bool HandleContextMenu(const ContextMenuParams& params);
 
+  // Callback for |RunJavaScrriptDialog|. The |success| value is true if the
+  // user responded with OK, |false| if the prompt was cancelled. The
+  // |user_input| value will exist for prompt alerts only.
+  typedef base::Callback<void(bool success, NSString* user_input)>
+      DialogClosedCallback;

[Eugene But (OOO till 7-30), 2016/06/24 17:04:53]

This looks exactly like a callback from DialogPresenter. Is there a way to share
the code?

[michaeldo, 2016/06/27 20:30:10]

I went with the duplication based on other callbacks, but I like the shared
definition better too. I moved it into javascript_dialog_callback.h in
/ios/web/public

+  // Notifies the delegate that a Javascript message needs handling.

[Eugene But (OOO till 7-30), 2016/06/24 17:04:52]

s/Javascript message needs handling/JavaScript dialog needs to be presented ?

[michaeldo, 2016/06/27 20:30:10]

Done.

+  void RunJavaScriptDialog(const GURL& origin_URL,

[Eugene But (OOO till 7-30), 2016/06/24 17:04:53]

s/origin_URL/origin_url

[michaeldo, 2016/06/27 20:30:10]

replaced with "origin" based on your previous comment.

+                           JavaScriptMessageType javascript_message_type,
+                           NSString* message_text,
+                           NSString* default_prompt_text,
+                           const DialogClosedCallback& callback);
+
+  // Callback for |RunAuthDialog|. If empty values are provided, the login will
+  // be rejected.
+  typedef base::Callback<void(const net::AuthCredentials& credentials)>
+      AuthDialogCallback;

[Eugene But (OOO till 7-30), 2016/06/24 17:04:52]

Same question. Is there a way to share this code?

[michaeldo, 2016/06/27 20:30:10]

This code is no longer part of this CL.

+  // Notifies the delegate that a response is needed to an HTTP Authentication
+  // prompt.
+  void RunAuthDialog(NSURLProtectionSpace* protectionSpace,
+                     NSURLCredential* credential,
+                     const AuthDialogCallback& callback);
+
+  // Cancels the display of any currently displayed dialog and any queued
+  // dialogs.
+  void CancelActiveAndPendingDialogs();
+
   // NavigationManagerDelegate:
   void NavigateToPendingEntry() override;
   void LoadURLWithParams(const NavigationManager::WebLoadParams&) override;