Let pyauto create an attached webdriver instance to manipulate web pages.

chrome/test/webdriver/automation.h

Index: chrome/test/webdriver/automation.h
diff --git a/chrome/test/webdriver/automation.h b/chrome/test/webdriver/automation.h
index 13e9228c134469c0d6ad7bdb371cbfc8b3a4efd0..7e216ce20247c779cd34446946adad11ba3d4629 100644
--- a/chrome/test/webdriver/automation.h
+++ b/chrome/test/webdriver/automation.h
@@ -9,6 +9,7 @@
 #include <string>
 #include <vector>
 
+#include "base/command_line.h"
 #include "base/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
@@ -17,7 +18,6 @@
 #include "ui/base/keycodes/keyboard_codes.h"
 
 class AutomationProxy;
-class CommandLine;
 class FilePath;
 class ProxyLauncher;
 struct WebKeyEvent;
@@ -42,19 +42,20 @@ class FramePath;
 // by posting a task from NewRunnableMethod.
 class Automation {
  public:
+  struct InitOptions {
+    InitOptions();
+    ~InitOptions();
+
+    CommandLine cmdline;
+    FilePath user_data_dir;
+    std::string channel_id;
+  };
+
   Automation();
   virtual ~Automation();
 
-  // Creates a browser, using the specified |browser_exe| and |user_data_dir|.
-  void InitWithBrowserPath(const FilePath& browser_exe,
-                           const FilePath& user_data_dir,
-                           const CommandLine& options,
-                           Error** error);
-
   // Start the system's default Chrome binary.
-  void Init(const CommandLine& options,
-            const FilePath& user_data_dir,
-            Error** error);
+  void Init(const InitOptions& options, Error** error);
 
   // Terminates this session and disconnects its automation proxy. After
   // invoking this method, the Automation can safely be deleted.