Add a metrics extensions API....

chrome/common/chrome_switches.h

 // 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.
 
 // Defines all the command-line switches used by Chrome.
 
 #ifndef CHROME_COMMON_CHROME_SWITCHES_H_
 #define CHROME_COMMON_CHROME_SWITCHES_H_
 
 #include "build/build_config.h"
@@ skipping 56 matching lines @@
 extern const char kDisableWebSockets[];
 extern const char kDisableXSSAuditor[];
 extern const char kDiskCacheDir[];
 extern const char kDiskCacheSize[];
 extern const char kDnsLogDetails[];
 extern const char kDnsPrefetchDisable[];
 extern const char kDomAutomationController[];
 extern const char kDumpHistogramsOnExit[];
 extern const char kEnableBenchmarking[];
 extern const char kEnableExperimentalExtensionApis[];
+extern const char kEnableMetricsExtensionApi[];
 extern const char kEnableExperimentalWebGL[];
 extern const char kEnableExtensionApps[];
 extern const char kEnableExtensionTimelineApi[];
 extern const char kEnableExtensionToolstrips[];
 extern const char kEnableFastback[];
 extern const char kEnableFileCookies[];
 extern const char kEnableGeolocation[];
 extern const char kEnableGPUPlugin[];
 extern const char kEnableIndexedDatabase[];
 extern const char kEnableIPv6[];
@@ skipping 160 matching lines @@
 extern const char kGearsPluginPathOverride[];
 extern const char kInvalidateSyncLogin[];
 #endif
 
 // DON'T ADD RANDOM STUFF HERE. Put it in the main section above in
 // alphabetical order, or in one of the ifdefs (also in order in each section).
 
 }  // namespace switches
 
 #endif  // CHROME_COMMON_CHROME_SWITCHES_H_