Bug 189378: add pref to disable plugins in the browser, r=josh

--HG--
extra : rebase_source : 7f70e2585d6b2840fa801969e5af50c5e81caca8

modules/plugin/base/src/nsPluginHost.cpp

@@ -1708,6 +1708,11 @@ nsPluginHost::nsPluginHost()
       mDefaultPluginDisabled = tmp;
     }
 
+    rv = mPrefService->GetBoolPref("plugin.disable", &tmp);
+    if (NS_SUCCEEDED(rv)) {
+      mPluginsDisabled = tmp;
+    }
+
 #ifdef WINCE
     mDefaultPluginDisabled = PR_TRUE;
 #endif
@@ -3694,6 +3699,9 @@ NS_IMETHODIMP nsPluginHost::LoadPlugins()
   if (mPluginsLoaded)
     return NS_OK;
 
+  if (mPluginsDisabled)
+    return NS_OK;
+
   PRBool pluginschanged;
   nsresult rv = FindPlugins(PR_TRUE, &pluginschanged);
   if (NS_FAILED(rv))

modules/plugin/base/src/nsPluginHost.h

@@ -259,6 +259,9 @@ private:
   // set by pref plugin.default_plugin_disabled
   PRPackedBool mDefaultPluginDisabled;
 
+  // set by pref plugin.disable
+  PRPackedBool mPluginsDisabled;
+
   nsPluginInstanceTagList mPluginInstanceTagList;
   nsTArray<PRLibrary*> mUnusedLibraries;