Split ProcessHandle and its related routines into base/process/process_handle.h.

base/base.gypi

Index: base/base.gypi
diff --git a/base/base.gypi b/base/base.gypi
index fad9e846254384b1124eb2c33c375ded2d98bab7..0808838898daa73e86897c7f22a2919643c2cd59 100644
--- a/base/base.gypi
+++ b/base/base.gypi
@@ -386,11 +386,8 @@
           'process_linux.cc',
           'process_posix.cc',
           'process_util.h',
-          'process_util_freebsd.cc',
           'process_util_ios.mm',
-          'process_util_linux.cc',
           'process_util_mac.mm',
-          'process_util_openbsd.cc',
           'process_util_posix.cc',
           'process_util_win.cc',
           'process_win.cc',
@@ -405,6 +402,12 @@
           'process/memory_linux.cc',
           'process/memory_mac.mm',
           'process/memory_win.cc',
+          'process/process_handle_freebsd.cc',
+          'process/process_handle_linux.cc',
+          'process/process_handle_mac.cc',
+          'process/process_handle_openbsd.cc',
+          'process/process_handle_posix.cc',
+          'process/process_handle_win.cc',
           'process/process_iterator.cc',
           'process/process_iterator.h',
           'process/process_iterator_freebsd.cc',
@@ -697,6 +700,7 @@
                'path_service.cc',
                'posix/unix_domain_socket_linux.cc',
                'process/kill_posix.cc',
+               'process/process_metrics_posix.cc',
                'process_posix.cc',
                'process_util.cc',
                'process_util_posix.cc',
@@ -725,6 +729,7 @@
               ['include', '^process_util_linux\\.cc$'],
               ['include', '^process/memory_linux\\.cc$'],
               ['include', '^process/internal_linux\\.cc$'],
+              ['include', '^process/process_handle_linux\\.cc$'],
               ['include', '^process/process_iterator\\.cc$'],
               ['include', '^process/process_iterator_linux\\.cc$'],
               ['include', '^process/process_metrics_linux\\.cc$'],
@@ -766,6 +771,7 @@
               ['exclude', '^process_util'],
               ['include', '^process_util_ios\\.mm$'],
               ['exclude', '^process/memory_mac\\.mm$'],
+              ['include', '^process/process_handle_posix\\.cc$'],
             ],
             'sources': [
               'process/memory_stubs.cc',