Implement Android UI of web notification inline replies

ui/message_center/notification.h

Index: ui/message_center/notification.h
diff --git a/ui/message_center/notification.h b/ui/message_center/notification.h
index f06e92dd29a5c191b933b975cc29341fc92e3a55..fd0f7a0ddfa894c2253e891b16b9e3b945806e2a 100644
--- a/ui/message_center/notification.h
+++ b/ui/message_center/notification.h
@@ -10,6 +10,7 @@
 #include <string>
 #include <vector>
 
+#include "base/strings/nullable_string16.h"
 #include "base/strings/string16.h"
 #include "base/time/time.h"
 #include "base/values.h"
@@ -22,6 +23,16 @@
 
 namespace message_center {
 
+// A Java counterpart will be generated for this enum.
+// GENERATED_JAVA_ENUM_PACKAGE: org.chromium.chrome.browser.notifications
+enum ButtonInfoType {
+  // Standard clickable button.
+  BUTTON_INFO_TYPE_BUTTON = 0,
+
+  // Action that supports an inline text reply.
+  BUTTON_INFO_TYPE_TEXT
+};
+
 struct MESSAGE_CENTER_EXPORT NotificationItem {
   base::string16 title;
   base::string16 message;
@@ -29,9 +40,13 @@ struct MESSAGE_CENTER_EXPORT NotificationItem {
   NotificationItem(const base::string16& title, const base::string16& message);
 };
 
+// TODO(nsatragno): rename to ActionInfo.
 struct MESSAGE_CENTER_EXPORT ButtonInfo {
+  // Defaults to BUTTON_INFO_TYPE_BUTTON.
+  ButtonInfoType type;
   base::string16 title;
   gfx::Image icon;
+  base::NullableString16 placeholder;
 
   ButtonInfo(const base::string16& title);
 };