Refactor: Make PyAuto InstallExtension() take a string. Delete dead code.

chrome/test/automation/automation_proxy.h

Index: chrome/test/automation/automation_proxy.h
diff --git a/chrome/test/automation/automation_proxy.h b/chrome/test/automation/automation_proxy.h
index 0390f033795b49f488e1a1a2c33f35cab8e62b29..ec87227163958025d66e8151763e58b31ed6a538 100644
--- a/chrome/test/automation/automation_proxy.h
+++ b/chrome/test/automation/automation_proxy.h
@@ -197,12 +197,12 @@ class AutomationProxy : public IPC::Channel::Listener,
   // sent.
   bool SavePackageShouldPromptUser(bool should_prompt) WARN_UNUSED_RESULT;
 
-  // Installs the extension crx. If |with_ui| is true an install confirmation
+  // Installs the extension. If |with_ui| is true an install confirmation
   // and notification UI is shown, otherwise the install is silent. Returns the
   // ExtensionProxy for the installed extension, or NULL on failure.
   // Note: Overinstalls and downgrades will return NULL.
-  scoped_refptr<ExtensionProxy> InstallExtension(const FilePath& crx_file,
-                                                 bool with_ui);
+  scoped_refptr<ExtensionProxy> InstallExtension(
+      const std::string& extension_path, bool with_ui);
 
   // Asserts that the next extension test result is true.
   void EnsureExtensionTestResult();