Introduce an extension parameter which is used to customize the extension. It's available for exter…

chrome/browser/extensions/extension_browsertest.h

Index: chrome/browser/extensions/extension_browsertest.h
diff --git a/chrome/browser/extensions/extension_browsertest.h b/chrome/browser/extensions/extension_browsertest.h
index 0588a21334839be31f5cb618778d999489c60db7..4cb3325cbcad7acb061da45d9ec536c8ba5418f8 100644
--- a/chrome/browser/extensions/extension_browsertest.h
+++ b/chrome/browser/extensions/extension_browsertest.h
@@ -80,13 +80,22 @@ class ExtensionBrowserTest : virtual public InProcessBrowserTest {
 
   const extensions::Extension* LoadExtension(const base::FilePath& path);
 
-  // Same as above, but enables the extension in incognito mode first.
+  // Load extension and enable it in incognito mode.
   const extensions::Extension* LoadExtensionIncognito(
       const base::FilePath& path);
 
+  // Load extension from the |path| folder. |flags| is bit mask of values from
+  // |Flags| enum.
   const extensions::Extension* LoadExtensionWithFlags(
       const base::FilePath& path, int flags);
 
+  // Same as above, but sets the installation parameter to the extension
+  // preferences.
+  const extensions::Extension* LoadExtensionWithInstallParam(
+      const base::FilePath& path,
+      int flags,
+      const std::string& install_param);
+
   // Loads unpacked extension from |path| with manifest |manifest_relative_path|
   // and imitates that it is a component extension.
   // |manifest_relative_path| is relative to |path|.