Remove the unmaintained performance monitor.

chrome/browser/performance_monitor/performance_monitor.gyp

Index: chrome/browser/performance_monitor/performance_monitor.gyp
diff --git a/chrome/browser/performance_monitor/performance_monitor.gyp b/chrome/browser/performance_monitor/performance_monitor.gyp
deleted file mode 100644
index 4739109fa1a0f3a8457cf71490417beaf6eba662..0000000000000000000000000000000000000000
--- a/chrome/browser/performance_monitor/performance_monitor.gyp
+++ /dev/null
@@ -1,26 +0,0 @@
-# Copyright (c) 2012 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.
-
-{
-  'targets': [
-    {
-      'target_name': 'performance_monitor',
-      'type': 'static_library',
-      'sources': [
-        '<@(schema_files)',
-      ],
-      'includes': [
-        '../../../build/json_schema_compile.gypi',
-      ],
-      'variables': {
-        'chromium_code': 1,
-        'schema_files': [
-          'events.json',
-        ],
-        'cc_dir': 'chrome/browser/performance_monitor',
-        'root_namespace': 'performance_monitor::%(namespace)s',
-      },
-    },
-  ],
-}