bug 820708 - refresh navigator.plugins when a plugin is enabled/disabled r=joshmoz

dom/base/Navigator.cpp

@@ -37,6 +37,7 @@
 #include "mozilla/ClearOnShutdown.h"
 #include "mozilla/StaticPtr.h"
 #include "Connection.h"
+#include "nsIObserverService.h"
 #ifdef MOZ_B2G_RIL
 #include "MobileConnection.h"
 #include "mozilla/dom/CellBroadcast.h"
@@ -102,6 +103,10 @@ Navigator::Navigator(nsPIDOMWindow* aWindow)
 {
   NS_ASSERTION(aWindow->IsInnerWindow(),
                "Navigator must get an inner window!");
+  nsCOMPtr<nsIObserverService> obsService =
+    mozilla::services::GetObserverService();
+  if (obsService)
+    obsService->AddObserver(this, "plugin-info-updated", false);
 }
 
 Navigator::~Navigator()
@@ -118,6 +123,7 @@ NS_INTERFACE_MAP_BEGIN(Navigator)
   NS_INTERFACE_MAP_ENTRY(nsINavigatorBattery)
   NS_INTERFACE_MAP_ENTRY(nsIDOMNavigatorDesktopNotification)
   NS_INTERFACE_MAP_ENTRY(nsIDOMMozNavigatorSms)
+  NS_INTERFACE_MAP_ENTRY(nsIObserver)
 #ifdef MOZ_MEDIA_NAVIGATOR
   NS_INTERFACE_MAP_ENTRY(nsINavigatorUserMedia)
   NS_INTERFACE_MAP_ENTRY(nsIDOMNavigatorUserMedia)
@@ -152,6 +158,12 @@ Navigator::Invalidate()
 {
   mWindow = nullptr;
 
+  nsCOMPtr<nsIObserverService> obsService =
+    mozilla::services::GetObserverService();
+  if (obsService) {
+    obsService->RemoveObserver(this, "plugin-info-updated");
+  }
+
   if (mPlugins) {
     mPlugins->Invalidate();
     mPlugins = nullptr;
@@ -248,6 +260,19 @@ Navigator::GetWindow()
   return win;
 }
 
+//*****************************************************************************
+//    Navigator::nsIObserver
+//*****************************************************************************
+
+NS_IMETHODIMP
+Navigator::Observe(nsISupports *aSubject, const char *aTopic,
+                   const PRUnichar *aData) {
+  if (!nsCRT::strcmp(aTopic, "plugin-info-updated") && mPlugins) {
+    mPlugins->Refresh(false);
+  }
+
+  return NS_OK;
+}
 
 //*****************************************************************************
 //    Navigator::nsIDOMNavigator

dom/base/Navigator.h

@@ -15,6 +15,7 @@
 #include "nsINavigatorBattery.h"
 #include "nsIDOMNavigatorSms.h"
 #include "nsIDOMNavigatorNetwork.h"
+#include "nsIObserver.h"
 #ifdef MOZ_AUDIO_CHANNEL_MANAGER
 #include "nsINavigatorAudioChannelManager.h"
 #endif
@@ -96,6 +97,7 @@ class Navigator : public nsIDOMNavigator
                 , public nsIDOMNavigatorDesktopNotification
                 , public nsINavigatorBattery
                 , public nsIDOMMozNavigatorSms
+                , public nsIObserver
 #ifdef MOZ_MEDIA_NAVIGATOR
                 , public nsINavigatorUserMedia
                 , public nsIDOMNavigatorUserMedia
@@ -132,6 +134,7 @@ public:
   NS_DECL_NSIDOMNAVIGATORDESKTOPNOTIFICATION
   NS_DECL_NSINAVIGATORBATTERY
   NS_DECL_NSIDOMMOZNAVIGATORSMS
+  NS_DECL_NSIOBSERVER
 #ifdef MOZ_MEDIA_NAVIGATOR
   NS_DECL_NSINAVIGATORUSERMEDIA
   NS_DECL_NSIDOMNAVIGATORUSERMEDIA

dom/base/nsPluginArray.cpp

@@ -186,8 +186,16 @@ nsPluginArray::Refresh(bool aReloadDocuments)
   // NS_ERROR_PLUGINS_PLUGINSNOTCHANGED on reloading plugins indicates
   // that plugins did not change and was not reloaded
   bool pluginsNotChanged = false;
-  if(mPluginHost)
-    pluginsNotChanged = (NS_ERROR_PLUGINS_PLUGINSNOTCHANGED == mPluginHost->ReloadPlugins(aReloadDocuments));
+  uint32_t currentPluginCount = 0;
+  if(mPluginHost) {
+    res = GetLength(&currentPluginCount);
+    NS_ENSURE_SUCCESS(res, res);
+    nsresult reloadResult = mPluginHost->ReloadPlugins(aReloadDocuments);
+    // currentPluginCount is as reported by nsPluginHost. mPluginCount is
+    // essentially a cache of this value, and may be out of date.
+    pluginsNotChanged = (reloadResult == NS_ERROR_PLUGINS_PLUGINSNOTCHANGED &&
+                         currentPluginCount == mPluginCount);
+  }
 
   // no need to reload the page if plugins have not been changed
   // in fact, if we do reload we can hit recursive load problem, see bug 93351

dom/plugins/base/nsPluginHost.cpp

@@ -2383,6 +2383,11 @@ nsPluginHost::UpdatePluginInfo(nsPluginTag* aPluginTag)
     RegisterWithCategoryManager(aPluginTag->mMimeTypes[i], shouldRegister);
   }
 
+  nsCOMPtr<nsIObserverService> obsService =
+    mozilla::services::GetObserverService();
+  if (obsService)
+    obsService->NotifyObservers(nullptr, "plugin-info-updated", nullptr);
+
   // Reload instances if needed
   if (aPluginTag->IsEnabled()) {
     return NS_OK;

dom/plugins/test/mochitest/Makefile.in

@@ -101,6 +101,7 @@ MOCHITEST_CHROME_FILES = \
   test_npruntime.xul   \
   test_wmode.xul \
   test_bug479979.xul \
+  test_refresh_navigator_plugins.html \
   $(NULL)
 
 ifndef MOZ_PER_WINDOW_PRIVATE_BROWSING

dom/plugins/test/mochitest/test_refresh_navigator_plugins.html

@@ -0,0 +1,62 @@
+<!DOCTYPE html>
+<!-- bug 820708 -->
+<html>
+  <head>
+    <meta><charset="utf-8"/>
+    <title>Test Refreshing navigator.plugins (bug 820708)</title>
+    <script type="application/javascript" src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+    <script type="application/javascript" src="chrome://mochikit/content/tests/SimpleTest/ChromeUtils.js"></script>
+  </head>
+  <body>
+    <script class="testbody" type="application/javascript">
+      SimpleTest.waitForExplicitFinish();
+      var pluginHost = Components.classes["@mozilla.org/plugin/host;1"]
+                       .getService(Components.interfaces.nsIPluginHost);
+      var pluginTags = pluginHost.getPluginTags();
+      var nextTest = null;
+      var obsService = Components.classes["@mozilla.org/observer-service;1"]
+                       .getService(Components.interfaces.nsIObserverService);
+      var observer = {
+        observe: function(aSubject, aTopic, aData) {
+          if (aTopic == "plugin-info-updated") {
+            SimpleTest.executeSoon(nextTest);
+          }
+        }
+      };
+      obsService.addObserver(observer, "plugin-info-updated", false);
+
+      var navTestPlugin = navigator.plugins.namedItem("Test Plug-in");
+      ok(navTestPlugin, "navigator.plugins should have Test Plug-in");
+      var tagTestPlugin = null;
+      for (var plugin of pluginTags) {
+        if (plugin.name == navTestPlugin.name) {
+          tagTestPlugin = plugin;
+          break;
+        }
+      }
+      ok(tagTestPlugin, "plugin tags should have Test Plug-in");
+      var mimeType = tagTestPlugin.getMimeTypes()[0];
+      ok(mimeType, "should have a MIME type for Test Plug-in");
+      ok(navigator.mimeTypes[mimeType.type], "navigator.mimeTypes should have an entry for '" + mimeType.type + "'");
+
+      nextTest = testPart2;
+      tagTestPlugin.disabled = true;
+
+      function testPart2() {
+        var navTestPlugin = navigator.plugins.namedItem("Test Plug-in");
+        ok(!navTestPlugin, "now navigator.plugins should not have Test Plug-in");
+        ok(!navigator.mimeTypes[mimeType.type], "now navigator.mimeTypes should not have an entry for '" + mimeType.type + "'");
+
+        nextTest = testPart3;
+        tagTestPlugin.disabled = false;
+      }
+
+      function testPart3() {
+        ok(navTestPlugin, "now navigator.plugins should have Test Plug-in again");
+        ok(navigator.mimeTypes[mimeType.type], "now navigator.mimeTypes should have an entry for '" + mimeType.type + "' again");
+        obsService.removeObserver(observer, "plugin-info-updated");
+        SimpleTest.finish();
+      }
+    </script>
+  </body>
+</html>