Force migrate all clients from multi-install back to single-install.

chrome/installer/util/master_preferences.h

Index: chrome/installer/util/master_preferences.h
diff --git a/chrome/installer/util/master_preferences.h b/chrome/installer/util/master_preferences.h
index 424c4dfdec6d2bfedc0ec8a8212b0382c71e3f06..c2ffc62c9c8eb73f0b0b0026971e667586bb8ebd 100644
--- a/chrome/installer/util/master_preferences.h
+++ b/chrome/installer/util/master_preferences.h
@@ -170,13 +170,9 @@ class MasterPreferences {
     return preferences_read_from_file_;
   }
 
-  bool install_chrome() const {
-    return chrome_;
-  }
+  bool install_chrome() const { return true; }
 
-  bool is_multi_install() const {
-    return multi_install_;
-  }
+  bool is_multi_install() const { return false; }
 
   // Returns a reference to this MasterPreferences' root dictionary of values.
   const base::DictionaryValue& master_dictionary() const {
@@ -197,8 +193,6 @@ class MasterPreferences {
   // string was successfully parsed.
   bool InitializeFromString(const std::string& json_data);
 
-  void InitializeProductFlags();
-
   // Enforces legacy preferences that should no longer be used, but could be
   // found in older master_preferences files.
   void EnforceLegacyPreferences();
@@ -209,10 +203,8 @@ class MasterPreferences {
   std::string ExtractPrefString(const std::string& name) const;
 
   std::unique_ptr<base::DictionaryValue> master_dictionary_;
-  base::DictionaryValue* distribution_;
-  bool preferences_read_from_file_;
-  bool chrome_;
-  bool multi_install_;
+  base::DictionaryValue* distribution_ = nullptr;
+  bool preferences_read_from_file_ = false;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MasterPreferences);