First part of automated_ui_tests improvements....

chrome/browser/automation/automation_provider.cc

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/automation/automation_provider.h"
 
 #include <set>
 
 #include "app/l10n_util.h"
 #include "app/message_box_flags.h"
@@ skipping 743 matching lines @@
     if (browser->command_updater()->SupportsCommand(command) &&
         browser->command_updater()->IsCommandEnabled(command)) {
       browser->ExecuteCommand(command);
       *success = true;
     }
   }
 }
 
 void AutomationProvider::ExecuteBrowserCommand(
     int handle, int command, IPC::Message* reply_message) {
+  // List of commands which just finish synchronously and don't require
+  // setting up an observer.
+  static const int kSynchronousCommands[] = {
+    IDC_HOME,
+    IDC_SELECT_NEXT_TAB,
+    IDC_SELECT_PREVIOUS_TAB,
+    IDC_SHOW_DOWNLOADS,
+    IDC_SHOW_HISTORY,
+  };
   if (browser_tracker_->ContainsHandle(handle)) {
     Browser* browser = browser_tracker_->GetResource(handle);
     if (browser->command_updater()->SupportsCommand(command) &&
         browser->command_updater()->IsCommandEnabled(command)) {
+      // First check if we can handle the command without using an observer.
+      for (size_t i = 0; i < arraysize(kSynchronousCommands); i++) {
+        if (command == kSynchronousCommands[i]) {
+          browser->ExecuteCommand(command);
+          AutomationMsg_WindowExecuteCommand::WriteReplyParams(reply_message,
+                                                               true);
+          Send(reply_message);
+          return;
+        }
+      }
+
+      // Use an observer if we have one, otherwise fail.
       if (ExecuteBrowserCommandObserver::CreateAndRegisterObserver(
           this, browser, command, reply_message)) {
         browser->ExecuteCommand(command);
         return;
       }
     }
   }
   AutomationMsg_WindowExecuteCommand::WriteReplyParams(reply_message, false);
   Send(reply_message);
 }
@@ skipping 1285 matching lines @@
   for (;iter != BrowserList::end(); ++iter) {
     gfx::NativeWindow this_window = (*iter)->window()->GetNativeHandle();
     if (window == this_window) {
       // Add() returns the existing handle for the resource if any.
       *browser_handle = browser_tracker_->Add(*iter);
       *success = true;
       return;
     }
   }
 }