Add test for Chrome install with existing Chrome Frame Multi-install

chrome/test/mini_installer_test/chrome_mini_installer.h

Index: chrome/test/mini_installer_test/chrome_mini_installer.h
diff --git a/chrome/test/mini_installer_test/chrome_mini_installer.h b/chrome/test/mini_installer_test/chrome_mini_installer.h
index 550eb41a3d00a91aa03cdd1fa06f95ed2b4078d2..7ecf4a0919f04a346588e2b2858ff52bb6e5e75d 100644
--- a/chrome/test/mini_installer_test/chrome_mini_installer.h
+++ b/chrome/test/mini_installer_test/chrome_mini_installer.h
@@ -26,9 +26,9 @@ class ChromeMiniInstaller {
     VERSION_FOLDER
   };
 
-  // This method returns path to either program files
-  // or documents and setting based on the install type.
-  bool GetChromeInstallDirectoryLocation(FilePath* path);
+  // Get the location at which Chrome or Chrome Frame is installed.
+  bool GetInstallDirectory(FilePath* path);
+
   // Get the base multi-install command.
   CommandLine GetBaseMultiInstallCommand();
 
@@ -122,7 +122,8 @@ class ChromeMiniInstaller {
   // Launch IE with |navigate_url|.
   void LaunchIE(const std::wstring& navigate_url);
 
-  // Run installer using provided |command|.
+  // Run installer with given |command|. If installer is
+  // system level append "--system-level" flag.
   void RunInstaller(const CommandLine& command);
 
   // Compares the registry key values after overinstall.