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

chrome/test/automation/proxy_launcher.h

Index: chrome/test/automation/proxy_launcher.h
diff --git a/chrome/test/automation/proxy_launcher.h b/chrome/test/automation/proxy_launcher.h
index 811366ba80c23e6b490c2222165a411e473d105c..09b13f4573b203e4875e178dd7a951fb84d0c0f9 100644
--- a/chrome/test/automation/proxy_launcher.h
+++ b/chrome/test/automation/proxy_launcher.h
@@ -286,11 +286,22 @@ class ProxyLauncher {
 // The channel id of the proxy is a constant specified by kInterfacePath.
 class NamedProxyLauncher : public ProxyLauncher {
  public:
-  // If launch_browser is true, launches Chrome with named interface enabled.
-  // Otherwise, there should be an existing instance the proxy can connect to.
+  struct InitParams {
+    // True if the browser should be launched. If false, this will connect
+    // to an already started Chrome.
+    bool launch_browser;
+
+    // True if we should disconnect on an IPC failure.
+    bool disconnect_on_failure;
+
+    // True if we should wait for Chrome's server channel to be initialized
+    // and listening. Only set to false if it is guaranteed the server channel
+    // is already listening.
+    bool wait_for_server_channel;

[Nirnimesh, 2011/08/01 19:21:24]

Why is this necessary? In what case would you set this to false?

[kkania, 2011/08/02 15:10:44]

This is necessary because the code for waiting for the server channel is broken
on windows. I have another CL that fixes that
(http://codereview.chromium.org/7486007), but it is going slowly and currently
waiting on Darin's comments.

Once that CL is in and I or dtu fixes a race in the named proxy launcher, I can
remove this arg.

I do not need to wait for the server channel for this CL because the
CreateNewAutomationProvider call guarantees the channel will be listening before
it returns (added a comment). It does so because ChannelProxy creates a
listening server channel in its constructor.

+  };
+
   NamedProxyLauncher(const std::string& channel_id,
-                     bool launch_browser,
-                     bool disconnect_on_failure);
+                     const InitParams& params);
 
   virtual AutomationProxy* CreateAutomationProxy(
       int execution_timeout) OVERRIDE;
@@ -301,9 +312,10 @@ class NamedProxyLauncher : public ProxyLauncher {
   virtual std::string PrefixedChannelID() const OVERRIDE;
 
  protected:
-  std::string channel_id_;      // Channel id of automation proxy.
-  bool launch_browser_;         // True if we should launch the browser too.
-  bool disconnect_on_failure_;  // True if we disconnect on IPC channel failure.
+  std::string channel_id_;        // Channel id of automation proxy.
+  bool launch_browser_;           // True if we should launch the browser too.
+  bool disconnect_on_failure_;    // True if we disconnect on channel failure.
+  bool wait_for_server_channel_;  // True if we should wait for server channel.
 
  private:
   DISALLOW_COPY_AND_ASSIGN(NamedProxyLauncher);