GN updates to build base on iOS

base/process/BUILD.gn

 # Copyright (c) 2015 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.
 
 source_set("process") {
   sources = [
     "internal_linux.cc",
     "internal_linux.h",
     "kill.cc",
     "kill.h",
@@ skipping 59 matching lines @@
     sources += [
       "internal_linux.cc",
       "memory_linux.cc",
       "process_handle_linux.cc",
       "process_iterator_linux.cc",
       "process_metrics_linux.cc",
     ]
     set_sources_assignment_filter(sources_assignment_filter)
   }
 
-  if (is_nacl) {
+  if (is_nacl || is_ios) {
     sources -= [
       "kill.cc",
       "kill.h",
       "kill_posix.cc",
       "launch.cc",
       "launch.h",
       "launch_posix.cc",
       "memory.cc",
       "memory.h",
       "process_iterator.cc",
       "process_iterator.h",
       "process_metrics.cc",
       "process_metrics_posix.cc",
       "process_posix.cc",
     ]
   }
 
+  if (is_ios) {
+    sources += [ "process_metrics.cc" ]
+  }
+
   configs += [ "//base:base_implementation" ]
 
   deps = [
     "//base/memory",
     "//base/third_party/dynamic_annotations",
   ]
 
   allow_circular_includes_from = [ "//base/memory" ]
 
   visibility = [ "//base/*" ]
 }