Bug 1288821 - Convert callObserver/removeObserver to native method; r=snorp

Combine the callObserver and removeObserver methods used for notifying
alert listeners into the native method
GeckoAppShell.notifyAlertListener. Keep track of the listener and the
alert cookie on the native side so that we don't need
GeckoAppShell.ALERT_COOKIES anymore.

mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java

@@ -179,8 +179,6 @@ public class GeckoAppShell
         return CRASH_HANDLER;
     }
 
-    private static final Map<String, String> ALERT_COOKIES = new ConcurrentHashMap<String, String>();
-
     private static volatile boolean locationHighAccuracyEnabled;
 
     // Accessed by NotificationHelper. This should be encapsulated.
@@ -1028,6 +1026,9 @@ public class GeckoAppShell
                                         PendingIntent.FLAG_UPDATE_CURRENT);
     }
 
+    @WrapForJNI
+    private static native void notifyAlertListener(String name, String topic);
+
     @WrapForJNI
     public static void showAlertNotification(String imageUrl, String alertTitle, String alertText,
                                              String alertCookie, String alertName, String host,
@@ -1042,8 +1043,7 @@ public class GeckoAppShell
                     notificationID, "persistent-notification-close", persistentData);
 
         } else {
-            ALERT_COOKIES.put(alertName, alertCookie);
-            callObserver(alertName, "alertshow", alertCookie);
+            notifyAlertListener(alertName, "alertshow");
 
             // The intent to launch when the user clicks the expanded notification
             final Intent notificationIntent = new Intent(GeckoApp.ACTION_ALERT_CALLBACK);
@@ -1072,13 +1072,7 @@ public class GeckoAppShell
 
     @WrapForJNI
     public static void closeNotification(String alertName) {
-        final String alertCookie = ALERT_COOKIES.get(alertName);
-        if (alertCookie != null) {
-            callObserver(alertName, "alertfinished", alertCookie);
-            ALERT_COOKIES.remove(alertName);
-        }
-
-        removeObserver(alertName);
+        notifyAlertListener(alertName, "alertfinished");
 
         final int notificationID = alertName.hashCode();
         notificationClient.remove(notificationID);
@@ -1088,7 +1082,7 @@ public class GeckoAppShell
         final int notificationID = alertName.hashCode();
 
         if (GeckoApp.ACTION_ALERT_CALLBACK.equals(action)) {
-            callObserver(alertName, "alertclickcallback", alertCookie);
+            notifyAlertListener(alertName, "alertclickcallback");
 
             if (notificationClient.isOngoing(notificationID)) {
                 // When clicked, keep the notification if it displays progress

widget/android/AndroidAlerts.cpp

@@ -6,13 +6,14 @@
 #include "AndroidAlerts.h"
 #include "GeneratedJNIWrappers.h"
 #include "nsAlertsUtils.h"
-#include "nsAppShell.h"
 
 namespace mozilla {
 namespace widget {
 
 NS_IMPL_ISUPPORTS(AndroidAlerts, nsIAlertsService)
 
+StaticAutoPtr<AndroidAlerts::AlertInfoMap> AndroidAlerts::sAlertInfoMap;
+
 NS_IMETHODIMP
 AndroidAlerts::ShowAlertNotification(const nsAString & aImageUrl,
                                      const nsAString & aAlertTitle,
@@ -76,8 +77,11 @@ AndroidAlerts::ShowPersistentNotification(const nsAString& aPersistentData,
     nsAlertsUtils::GetSourceHostPort(principal, host);
 
     if (aPersistentData.IsEmpty() && aAlertListener) {
-        // This will remove any observers already registered for this id
-        nsAppShell::PostEvent(AndroidGeckoEvent::MakeAddObserver(name, aAlertListener));
+        if (!sAlertInfoMap) {
+            sAlertInfoMap = new AlertInfoMap();
+        }
+        // This will remove any observers already registered for this name.
+        sAlertInfoMap->Put(name, new AlertInfo{aAlertListener, cookie});
     }
 
     java::GeckoAppShell::ShowAlertNotification(
@@ -91,9 +95,33 @@ NS_IMETHODIMP
 AndroidAlerts::CloseAlert(const nsAString& aAlertName,
                           nsIPrincipal* aPrincipal)
 {
+    // We delete the entry in sAlertInfoMap later, when CloseNotification calls
+    // NotifyListener.
     java::GeckoAppShell::CloseNotification(aAlertName);
     return NS_OK;
 }
 
+void
+AndroidAlerts::NotifyListener(const nsAString& aName, const char* aTopic)
+{
+    if (!sAlertInfoMap) {
+        return;
+    }
+
+    const auto pAlertInfo = sAlertInfoMap->Get(aName);
+    if (!pAlertInfo) {
+        return;
+    }
+
+    if (pAlertInfo->listener) {
+        pAlertInfo->listener->Observe(
+                nullptr, aTopic, pAlertInfo->cookie.get());
+    }
+
+    if (NS_LITERAL_CSTRING("alertfinished").Equals(aTopic)) {
+        sAlertInfoMap->Remove(aName);
+    }
+}
+
 } // namespace widget
 } // namespace mozilla

widget/android/AndroidAlerts.h

@@ -6,7 +6,13 @@
 #ifndef mozilla_widget_AndroidAlerts_h__
 #define mozilla_widget_AndroidAlerts_h__
 
+#include "nsClassHashtable.h"
+#include "nsCOMPtr.h"
+#include "nsHashKeys.h"
 #include "nsIAlertsService.h"
+#include "nsIObserver.h"
+
+#include "mozilla/StaticPtr.h"
 
 namespace mozilla {
 namespace widget {
@@ -19,8 +25,22 @@ public:
 
   AndroidAlerts() {}
 
+  static void NotifyListener(const nsAString& aName, const char* aTopic);
+
 protected:
-  virtual ~AndroidAlerts() {}
+  virtual ~AndroidAlerts()
+  {
+      sAlertInfoMap = nullptr;
+  }
+
+  struct AlertInfo
+  {
+      nsCOMPtr<nsIObserver> listener;
+      nsString cookie;
+  };
+
+  using AlertInfoMap = nsClassHashtable<nsStringHashKey, AlertInfo>;
+  static StaticAutoPtr<AlertInfoMap> sAlertInfoMap;
 };
 
 } // namespace widget

widget/android/nsAppShell.cpp

@@ -53,6 +53,7 @@
 #include "mozilla/Logging.h"
 #endif
 
+#include "AndroidAlerts.h"
 #include "ANRReporter.h"
 #include "GeckoNetworkManager.h"
 #include "GeckoScreenOrientation.h"
@@ -322,6 +323,17 @@ public:
         }
 #endif
     }
+
+    static void NotifyAlertListener(jni::String::Param aName,
+                                    jni::String::Param aTopic)
+    {
+        if (!aName || !aTopic) {
+            return;
+        }
+
+        AndroidAlerts::NotifyListener(
+                aName->ToString(), aTopic->ToCString().get());
+    }
 };
 
 nsAppShell::nsAppShell()