Remove ALL usage of CriticalSectionWrapper.

webrtc/system_wrappers/BUILD.gn

Index: webrtc/system_wrappers/BUILD.gn
diff --git a/webrtc/system_wrappers/BUILD.gn b/webrtc/system_wrappers/BUILD.gn
index 83f5f23d1f796898d94737ba85e1515d590e210f..708fd318f0f6272cce9da2672a91b29500297c1e 100644
--- a/webrtc/system_wrappers/BUILD.gn
+++ b/webrtc/system_wrappers/BUILD.gn
@@ -20,7 +20,6 @@ rtc_static_library("system_wrappers") {
     "include/clock.h",
     "include/cpu_features_wrapper.h",
     "include/cpu_info.h",
-    "include/critical_section_wrapper.h",
     "include/event_wrapper.h",
     "include/field_trial.h",
     "include/file_wrapper.h",
@@ -38,8 +37,6 @@ rtc_static_library("system_wrappers") {
     "source/aligned_malloc.cc",
     "source/atomic32_win.cc",
     "source/clock.cc",
-    "source/condition_variable_event_win.cc",
-    "source/condition_variable_event_win.h",
     "source/cpu_features.cc",
     "source/cpu_info.cc",
     "source/event.cc",
@@ -55,8 +52,6 @@ rtc_static_library("system_wrappers") {
     "source/rw_lock_posix.h",
     "source/rw_lock_win.cc",
     "source/rw_lock_win.h",
-    "source/rw_lock_winxp_win.cc",
-    "source/rw_lock_winxp_win.h",
     "source/sleep.cc",
     "source/timestamp_extrapolator.cc",
     "source/trace_impl.cc",
@@ -171,8 +166,6 @@ if (rtc_include_tests) {
       "source/aligned_array_unittest.cc",
       "source/aligned_malloc_unittest.cc",
       "source/clock_unittest.cc",
-      "source/condition_variable_unittest.cc",
-      "source/critical_section_unittest.cc",
       "source/event_timer_posix_unittest.cc",
       "source/logging_unittest.cc",
       "source/metrics_default_unittest.cc",