[Mac]Implement ViewID support.

chrome/browser/cocoa/find_bar_view.mm

Index: chrome/browser/cocoa/find_bar_view.mm
diff --git a/chrome/browser/cocoa/find_bar_view.mm b/chrome/browser/cocoa/find_bar_view.mm
index deb4d585eae761acccc5de9e40d15ed692d44d8d..14529f6b11f166952046ecbdfeb6961b05a15de7 100644
--- a/chrome/browser/cocoa/find_bar_view.mm
+++ b/chrome/browser/cocoa/find_bar_view.mm
@@ -1,10 +1,11 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// 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.
 
 #import "chrome/browser/cocoa/find_bar_view.h"
 
 #import "chrome/browser/cocoa/themed_window.h"
+#import "chrome/browser/cocoa/view_id_util.h"
 
 namespace {
 CGFloat kCurveSize = 8;
@@ -111,4 +112,10 @@ CGFloat kCurveSize = 8;
 
 - (void)otherMouseDragged:(NSEvent *)theEvent {
 }
+
+// Tag is used solely for ViewID. Override to prevent changing of it.
+- (NSInteger)tag {
+  return view_id_util::ViewIDToTag(VIEW_ID_FIND_IN_PAGE);
+}
+
 @end