Split infobar_delegate.[cc,h] into separate pieces for the different classes defined within, so that

chrome/browser/tab_contents/link_infobar_delegate.cc

Index: chrome/browser/tab_contents/link_infobar_delegate.cc
diff --git a/chrome/browser/tab_contents/link_infobar_delegate.cc b/chrome/browser/tab_contents/link_infobar_delegate.cc
new file mode 100644
index 0000000000000000000000000000000000000000..8410dec258532cc1408fe6d1dfb3a07918099c40
--- /dev/null
+++ b/chrome/browser/tab_contents/link_infobar_delegate.cc
@@ -0,0 +1,22 @@
+// Copyright (c) 2011 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/tab_contents/link_infobar_delegate.h"
+
+#include "content/browser/tab_contents/tab_contents.h"
+
+bool LinkInfoBarDelegate::LinkClicked(WindowOpenDisposition disposition) {
+  return true;
+}
+
+LinkInfoBarDelegate::LinkInfoBarDelegate(TabContents* contents)
+    : InfoBarDelegate(contents) {
+}
+
+LinkInfoBarDelegate::~LinkInfoBarDelegate() {
+}
+
+LinkInfoBarDelegate* LinkInfoBarDelegate::AsLinkInfoBarDelegate() {
+  return this;
+}