This is an alternate CL to the fix in http://codereview.chromium.org/5553002.

chrome/browser/ui/find_bar/find_bar_controller.cc

 // Copyright (c) 2010 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/ui/find_bar/find_bar_controller.h"
 
 #include <algorithm>
 
 #include "base/i18n/rtl.h"
 #include "build/build_config.h"
@@ skipping 74 matching lines @@
 
   MaybeSetPrepopulateText();
 
   if (tab_contents_->find_ui_active()) {
     // A tab with a visible find bar just got selected and we need to show the
     // find bar but without animation since it was already animated into its
     // visible state. We also want to reset the window location so that
     // we don't surprise the user by popping up to the left for no apparent
     // reason.
     find_bar_->Show(false);
+    find_bar_->SetFocusAndSelection();
   }
 
   UpdateFindBarForCurrentResult();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // FindBarHost, NotificationObserver implementation:
 
 void FindBarController::Observe(NotificationType type,
                                 const NotificationSource& source,
@@ skipping 114 matching lines @@
   // shown it is showing the right state for this tab. We update the find text
   // _first_ since the FindBarView checks its emptiness to see if it should
   // clear the result count display when there's nothing in the box.
   find_bar_->SetFindText(find_string);
 #else
   // Having a per-tab find_string is not compatible with OS X's find pasteboard,
   // so we always have the same find text in all find bars. This is done through
   // the find pasteboard mechanism, so don't set the text here.
 #endif
 }