Sequentialize calls to PluginList::GetPlugins from PluginService.

BUG=105987
TEST=none


Review URL: https://chromiumcodereview.appspot.com/10381087

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@137396 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 16 insertions, 7 deletions

diff --git a/webkit/plugins/npapi/plugin_list.h b/webkit/plugins/npapi/plugin_list.h
index d01b38f..a948782 100644
--- a/webkit/plugins/npapi/plugin_list.h
+++ b/webkit/plugins/npapi/plugin_list.h
@@ -121,7 +121,7 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
       const string16& mime_type_descriptions,
       std::vector<webkit::WebPluginMimeType>* parsed_mime_types);
 
-  // Get all the plugins synchronously.
+  // Get all the plugins synchronously, loading them if necessary.
   void GetPlugins(std::vector<webkit::WebPluginInfo>* plugins);
 
   // Returns true if the list of plugins is cached and is copied into the out
@@ -195,6 +195,17 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
                                  ScopedVector<PluginGroup>* plugin_groups);
 
  private:
+  enum LoadingState {
+    LOADING_STATE_NEEDS_REFRESH,
+    LOADING_STATE_REFRESHING,
+    LOADING_STATE_UP_TO_DATE,
+  };
+
+  struct InternalPlugin {
+    webkit::WebPluginInfo info;
+    PluginEntryPoints entry_points;
+  };
+
   friend class PluginListTest;
   friend struct base::DefaultLazyInstanceTraits<PluginList>;
   FRIEND_TEST_ALL_PREFIXES(PluginGroupTest, PluginGroupDefinition);
@@ -268,8 +279,10 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
   // Internals
   //
 
-  // If true, we reload plugins even if they've been loaded already.
-  bool plugins_need_refresh_;
+  // States whether we will load the plug-in list the next time we try to access
+  // it, whether we are currently in the process of loading it, or whether we
+  // consider it up-to-date.
+  LoadingState loading_state_;
 
   // Extra plugin paths that we want to search when loading.
   std::vector<FilePath> extra_plugin_paths_;
@@ -277,10 +290,6 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
   // Extra plugin directories that we want to search when loading.
   std::vector<FilePath> extra_plugin_dirs_;
 
-  struct InternalPlugin {
-    webkit::WebPluginInfo info;
-    PluginEntryPoints entry_points;
-  };
   // Holds information about internal plugins.
   std::vector<InternalPlugin> internal_plugins_;