Bug 1441810 - Ensure session save/restore works even if no ContentDelegate is set. r=jchen

mobile/android/chrome/geckoview/GeckoViewContent.js

@@ -41,11 +41,6 @@ class GeckoViewContent extends GeckoViewContentModule {
                                            this);
     this.messageManager.addMessageListener("GeckoView:ZoomToInput",
                                            this);
-
-    this.progressFilter =
-      Cc["@mozilla.org/appshell/component/browser-status-filter;1"]
-      .createInstance(Ci.nsIWebProgress);
-    this.flags = Ci.nsIWebProgress.NOTIFY_LOCATION;
   }
 
   onDisable() {
@@ -206,6 +201,13 @@ class GeckoViewContent extends GeckoViewContentModule {
           addEventListener("load", this, {capture: true, mozSystemGroup: true, once: true});
           addEventListener("pageshow", this, {capture: true, mozSystemGroup: true, once: true});
 
+          if (!this.progressFilter) {
+            this.progressFilter =
+              Cc["@mozilla.org/appshell/component/browser-status-filter;1"]
+              .createInstance(Ci.nsIWebProgress);
+            this.flags = Ci.nsIWebProgress.NOTIFY_LOCATION;
+          }
+
           this.progressFilter.addProgressListener(this, this.flags);
           let webProgress = docShell.QueryInterface(Ci.nsIInterfaceRequestor)
                                     .getInterface(Ci.nsIWebProgress);

mobile/android/modules/geckoview/GeckoViewContent.jsm

@@ -16,6 +16,8 @@ class GeckoViewContent extends GeckoViewModule {
       "GeckoView:SaveState",
       "GeckoView:RestoreState"
     ]);
+
+    this.messageManager.addMessageListener("GeckoView:SaveStateFinish", this);
   }
 
   onEnable() {
@@ -33,7 +35,6 @@ class GeckoViewContent extends GeckoViewModule {
 
     this.messageManager.addMessageListener("GeckoView:DOMFullscreenExit", this);
     this.messageManager.addMessageListener("GeckoView:DOMFullscreenRequest", this);
-    this.messageManager.addMessageListener("GeckoView:SaveStateFinish", this);
   }
 
   onDisable() {