Added GetCpuTime to base/ to get total CPU time consumed by process for perf tests.

webrtc/base/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("//build/config/crypto.gni")
 import("//build/config/ui.gni")
@@ skipping 670 matching lines @@
       # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
       suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
     }
   }
 
   rtc_source_set("rtc_base_tests_utils") {
     testonly = true
     sources = [
       # Also use this as a convenient dumping ground for misc files that are
       # included by multiple targets below.
+      "cpu_time.cc",
+      "cpu_time.h",
       "fakeclock.cc",
       "fakeclock.h",
       "fakenetwork.h",
       "fakesslidentity.h",
       "firewallsocketserver.cc",
       "firewallsocketserver.h",
       "gunit.h",
       "httpserver.cc",
       "httpserver.h",
       "natserver.cc",
@@ skipping 25 matching lines @@
 
     if (!build_with_chromium && is_clang) {
       # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
       suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
     }
   }
 
   rtc_source_set("rtc_base_nonparallel_tests") {
     testonly = true
     sources = [
+      "cpu_time_unittest.cc",
       "filerotatingstream_unittest.cc",
       "nullsocketserver_unittest.cc",
       "physicalsocketserver_unittest.cc",
       "socket_unittest.cc",
       "socket_unittest.h",
       "socketaddress_unittest.cc",
       "virtualsocket_unittest.cc",
     ]
     deps = [
       ":rtc_base",
@@ skipping 158 matching lines @@
 
 if (is_android) {
   android_library("base_java") {
     java_files = [
       "java/src/org/webrtc/Logging.java",
       "java/src/org/webrtc/Size.java",
       "java/src/org/webrtc/ThreadUtils.java",
     ]
   }
 }