Remove dependency of plugin infobar delegates on PluginObserver.

chrome/browser/plugins/plugin_infobar_delegates.h

Index: chrome/browser/plugins/plugin_infobar_delegates.h
diff --git a/chrome/browser/plugins/plugin_infobar_delegates.h b/chrome/browser/plugins/plugin_infobar_delegates.h
index 2a829d9adf48a899f6946e4b45f915f56a54bdb1..08937d743a20bd220a3fd0097da7199a12504430 100644
--- a/chrome/browser/plugins/plugin_infobar_delegates.h
+++ b/chrome/browser/plugins/plugin_infobar_delegates.h
@@ -15,7 +15,10 @@
 
 class InfoBarService;
 class HostContentSettingsMap;
-class PluginObserver;
+
+namespace content {
+class WebContents;
+}
 
 // Base class for blocked plug-in infobars.
 class PluginInfoBarDelegate : public ConfirmInfoBarDelegate {
@@ -76,11 +79,11 @@ class UnauthorizedPluginInfoBarDelegate : public PluginInfoBarDelegate {
 class OutdatedPluginInfoBarDelegate : public PluginInfoBarDelegate,
                                       public WeakPluginInstallerObserver {
  public:
-  static InfoBarDelegate* Create(PluginObserver* observer,
+  static InfoBarDelegate* Create(content::WebContents* web_contents,
                                  PluginInstaller* installer);
 
  private:
-  OutdatedPluginInfoBarDelegate(PluginObserver* observer,
+  OutdatedPluginInfoBarDelegate(content::WebContents* web_contents,
                                 PluginInstaller* installer,
                                 const string16& message);
   virtual ~OutdatedPluginInfoBarDelegate();
@@ -107,10 +110,6 @@ class OutdatedPluginInfoBarDelegate : public PluginInfoBarDelegate,
   // not have any buttons (and not call the callback).
   void ReplaceWithInfoBar(const string16& message);
 
-  // Has the same lifetime as TabContents, which owns us
-  // (transitively via InfoBarService).
-  PluginObserver* observer_;
-
   string16 message_;
 
   DISALLOW_COPY_AND_ASSIGN(OutdatedPluginInfoBarDelegate);