Certificate Transparency: Wire the TreeStateTracker up.

chrome/browser/component_updater/sth_set_component_installer.h

Index: chrome/browser/component_updater/sth_set_component_installer.h
diff --git a/chrome/browser/component_updater/sth_set_component_installer.h b/chrome/browser/component_updater/sth_set_component_installer.h
index 4223aa371d544d355d2d13685196b8e28d09f46f..1279706481c10fd0152be8050aa83a0d2d0bf628 100644
--- a/chrome/browser/component_updater/sth_set_component_installer.h
+++ b/chrome/browser/component_updater/sth_set_component_installer.h
@@ -40,8 +40,7 @@ class ComponentUpdateService;
 class STHSetComponentInstallerTraits : public ComponentInstallerTraits {
  public:
   // The |sth_distributor| will be notified each time a new STH is observed.
-  explicit STHSetComponentInstallerTraits(
-      std::unique_ptr<net::ct::STHObserver> sth_observer);
+  explicit STHSetComponentInstallerTraits(net::ct::STHObserver* sth_observer);
   ~STHSetComponentInstallerTraits() override;
 
  private:
@@ -73,7 +72,10 @@ class STHSetComponentInstallerTraits : public ComponentInstallerTraits {
   // STH parsing failed - do nothing.
   void OnJsonParseError(const std::string& log_id, const std::string& error);
 
-  std::unique_ptr<net::ct::STHObserver> sth_observer_;
+  // The observer is not owned by this class, so the code creating an instance
+  // of this class is expected to ensure the STHObserver lives as long as
+  // this class does. Typically the observer provided will be a global.
+  net::ct::STHObserver* sth_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(STHSetComponentInstallerTraits);
 };