Revert of Safe numeric library: base/numerics (copied from Chromium)

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 123 matching lines @@
     "platform_file.cc",
     "platform_file.h",
     "platform_thread.cc",
     "platform_thread.h",
     "platform_thread_types.h",
     "random.cc",
     "random.h",
     "rate_statistics.cc",
     "rate_statistics.h",
     "refcount.h",
+    "safe_conversions.h",
+    "safe_conversions_impl.h",
     "scoped_ptr.h",
     "scoped_ref_ptr.h",
     "stringencode.cc",
     "stringencode.h",
     "stringutils.cc",
     "stringutils.h",
     "systeminfo.cc",
     "systeminfo.h",
     "template_util.h",
     "thread_annotations.h",
@@ skipping 18 matching lines @@
       "logging.cc",
       "logging.h",
     ]
   }
 }
 
 static_library("rtc_base") {
   cflags = []
   cflags_cc = []
   libs = []
+  deps = []
+  public_deps = [
+    ":rtc_base_approved",
+  ]
 
   configs += [
     "..:common_config",
     ":rtc_base_config",
   ]
 
   public_configs = [
     "..:common_inherited_config",
     ":rtc_base_config",
   ]
 
   defines = [ "LOGGING=1" ]
 
-  deps = [
-    ":safe_numerics",
-  ]
-  public_deps = [
-    ":rtc_base_approved",
-  ]
-
   sources = [
     "arraysize.h",
     "asyncfile.cc",
     "asyncfile.h",
     "asyncinvoker-inl.h",
     "asyncinvoker.cc",
     "asyncinvoker.h",
     "asyncpacketsocket.cc",
     "asyncpacketsocket.h",
     "asyncresolverinterface.cc",
@@ skipping 439 matching lines @@
       "objc/RTCTracing.mm",
     ]
   }
 }
 
 source_set("gtest_prod") {
   sources = [
     "gtest_prod_util.h",
   ]
 }
-
-# GYP version: webrtc/base/base.gyp:safe_numerics
-source_set("safe_numerics") {
-  deps = [
-    ":rtc_base_approved",
-  ]
-  sources = [
-    "numerics/safe_conversions.h",
-    "numerics/safe_conversions_impl.h",
-    "numerics/safe_math.h",
-    "numerics/safe_math_impl.h",
-  ]
-}