diff --git a/base/PRESUBMIT.py b/base/PRESUBMIT.py
deleted file mode 100644
index 7fc8107..0000000
--- a/base/PRESUBMIT.py
+++ /dev/null
@@ -1,49 +0,0 @@
-# Copyright (c) 2012 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.
-
-"""Chromium presubmit script for src/base.
-
-See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
-for more details on the presubmit API built into depot_tools.
-"""
-
-def _CheckNoInterfacesInBase(input_api, output_api):
-  """Checks to make sure no files in libbase.a have |@interface|."""
-  pattern = input_api.re.compile(r'^\s*@interface', input_api.re.MULTILINE)
-  files = []
-  for f in input_api.AffectedSourceFiles(input_api.FilterSourceFile):
-    if (f.LocalPath().startswith('base/') and
-        not "/ios/" in f.LocalPath() and
-        not "/test/" in f.LocalPath() and
-        not f.LocalPath().endswith('_unittest.mm') and
-        not f.LocalPath().endswith('mac/sdk_forward_declarations.h')):
-      contents = input_api.ReadFile(f)
-      if pattern.search(contents):
-        files.append(f)
-
-  if len(files):
-    return [ output_api.PresubmitError(
-        'Objective-C interfaces or categories are forbidden in libbase. ' +
-        'See http://groups.google.com/a/chromium.org/group/chromium-dev/' +
-        'browse_thread/thread/efb28c10435987fd',
-        files) ]
-  return []
-
-
-def _CommonChecks(input_api, output_api):
-  """Checks common to both upload and commit."""
-  results = []
-  results.extend(_CheckNoInterfacesInBase(input_api, output_api))
-  return results
-
-def CheckChangeOnUpload(input_api, output_api):
-  results = []
-  results.extend(_CommonChecks(input_api, output_api))
-  return results
-
-
-def CheckChangeOnCommit(input_api, output_api):
-  results = []
-  results.extend(_CommonChecks(input_api, output_api))
-  return results
diff --git a/base/barrier_closure.cc b/base/barrier_closure.cc
deleted file mode 100644
index 4426bb9..0000000
--- a/base/barrier_closure.cc
+++ /dev/null
@@ -1,51 +0,0 @@
-// Copyright 2013 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.
-
-#include "base/barrier_closure.h"
-
-#include <utility>
-
-#include "base/atomic_ref_count.h"
-#include "base/bind.h"
-#include "base/memory/ptr_util.h"
-
-namespace base {
-namespace {
-
-// Maintains state for a BarrierClosure.
-class BarrierInfo {
- public:
-  BarrierInfo(int num_callbacks_left, OnceClosure done_closure);
-  void Run();
-
- private:
-  AtomicRefCount num_callbacks_left_;
-  OnceClosure done_closure_;
-};
-
-BarrierInfo::BarrierInfo(int num_callbacks, OnceClosure done_closure)
-    : num_callbacks_left_(num_callbacks),
-      done_closure_(std::move(done_closure)) {}
-
-void BarrierInfo::Run() {
-  DCHECK(!num_callbacks_left_.IsZero());
-  if (!num_callbacks_left_.Decrement())
-    std::move(done_closure_).Run();
-}
-
-}  // namespace
-
-RepeatingClosure BarrierClosure(int num_callbacks_left,
-                                OnceClosure done_closure) {
-  DCHECK_GE(num_callbacks_left, 0);
-
-  if (num_callbacks_left == 0)
-    std::move(done_closure).Run();
-
-  return BindRepeating(
-      &BarrierInfo::Run,
-      Owned(new BarrierInfo(num_callbacks_left, std::move(done_closure))));
-}
-
-}  // namespace base
diff --git a/base/barrier_closure.h b/base/barrier_closure.h
deleted file mode 100644
index 282aa39..0000000
--- a/base/barrier_closure.h
+++ /dev/null
@@ -1,28 +0,0 @@
-// Copyright 2013 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.
-
-#ifndef BASE_BARRIER_CLOSURE_H_
-#define BASE_BARRIER_CLOSURE_H_
-
-#include "base/base_export.h"
-#include "base/callback.h"
-
-namespace base {
-
-// BarrierClosure executes |done_closure| after it has been invoked
-// |num_closures| times.
-//
-// If |num_closures| is 0, |done_closure| is executed immediately.
-//
-// BarrierClosure is thread-safe - the count of remaining closures is
-// maintained as a base::AtomicRefCount. |done_closure| will be run on
-// the thread that calls the final Run() on the returned closures.
-//
-// |done_closure| is also cleared on the final calling thread.
-BASE_EXPORT RepeatingClosure BarrierClosure(int num_closures,
-                                            OnceClosure done_closure);
-
-}  // namespace base
-
-#endif  // BASE_BARRIER_CLOSURE_H_
diff --git a/base/big_endian.cc b/base/big_endian.cc
deleted file mode 100644
index 514581f..0000000
--- a/base/big_endian.cc
+++ /dev/null
@@ -1,105 +0,0 @@
-// Copyright 2014 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.
-
-#include "base/big_endian.h"
-
-#include "base/strings/string_piece.h"
-
-namespace base {
-
-BigEndianReader::BigEndianReader(const char* buf, size_t len)
-    : ptr_(buf), end_(ptr_ + len) {}
-
-bool BigEndianReader::Skip(size_t len) {
-  if (ptr_ + len > end_)
-    return false;
-  ptr_ += len;
-  return true;
-}
-
-bool BigEndianReader::ReadBytes(void* out, size_t len) {
-  if (ptr_ + len > end_)
-    return false;
-  memcpy(out, ptr_, len);
-  ptr_ += len;
-  return true;
-}
-
-bool BigEndianReader::ReadPiece(base::StringPiece* out, size_t len) {
-  if (ptr_ + len > end_)
-    return false;
-  *out = base::StringPiece(ptr_, len);
-  ptr_ += len;
-  return true;
-}
-
-template<typename T>
-bool BigEndianReader::Read(T* value) {
-  if (ptr_ + sizeof(T) > end_)
-    return false;
-  ReadBigEndian<T>(ptr_, value);
-  ptr_ += sizeof(T);
-  return true;
-}
-
-bool BigEndianReader::ReadU8(uint8_t* value) {
-  return Read(value);
-}
-
-bool BigEndianReader::ReadU16(uint16_t* value) {
-  return Read(value);
-}
-
-bool BigEndianReader::ReadU32(uint32_t* value) {
-  return Read(value);
-}
-
-bool BigEndianReader::ReadU64(uint64_t* value) {
-  return Read(value);
-}
-
-BigEndianWriter::BigEndianWriter(char* buf, size_t len)
-    : ptr_(buf), end_(ptr_ + len) {}
-
-bool BigEndianWriter::Skip(size_t len) {
-  if (ptr_ + len > end_)
-    return false;
-  ptr_ += len;
-  return true;
-}
-
-bool BigEndianWriter::WriteBytes(const void* buf, size_t len) {
-  if (ptr_ + len > end_)
-    return false;
-  memcpy(ptr_, buf, len);
-  ptr_ += len;
-  return true;
-}
-
-template<typename T>
-bool BigEndianWriter::Write(T value) {
-  if (ptr_ + sizeof(T) > end_)
-    return false;
-  WriteBigEndian<T>(ptr_, value);
-  ptr_ += sizeof(T);
-  return true;
-}
-
-bool BigEndianWriter::WriteU8(uint8_t value) {
-  return Write(value);
-}
-
-bool BigEndianWriter::WriteU16(uint16_t value) {
-  return Write(value);
-}
-
-bool BigEndianWriter::WriteU32(uint32_t value) {
-  return Write(value);
-}
-
-bool BigEndianWriter::WriteU64(uint64_t value) {
-  return Write(value);
-}
-
-}  // namespace base
diff --git a/base/big_endian.h b/base/big_endian.h
deleted file mode 100644
index 5684c67..0000000
--- a/base/big_endian.h
+++ /dev/null
@@ -1,106 +0,0 @@
-// Copyright 2014 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.
-
-#ifndef BASE_BIG_ENDIAN_H_
-#define BASE_BIG_ENDIAN_H_
-
-#include <stddef.h>
-#include <stdint.h>
-
-#include "base/base_export.h"
-#include "base/strings/string_piece.h"
-
-namespace base {
-
-// Read an integer (signed or unsigned) from |buf| in Big Endian order.
-// Note: this loop is unrolled with -O1 and above.
-// NOTE(szym): glibc dns-canon.c use ntohs(*(uint16_t*)ptr) which is
-// potentially unaligned.
-// This would cause SIGBUS on ARMv5 or earlier and ARMv6-M.
-template<typename T>
-inline void ReadBigEndian(const char buf[], T* out) {
-  *out = buf[0];
-  for (size_t i = 1; i < sizeof(T); ++i) {
-    *out <<= 8;
-    // Must cast to uint8_t to avoid clobbering by sign extension.
-    *out |= static_cast<uint8_t>(buf[i]);
-  }
-}
-
-// Write an integer (signed or unsigned) |val| to |buf| in Big Endian order.
-// Note: this loop is unrolled with -O1 and above.
-template<typename T>
-inline void WriteBigEndian(char buf[], T val) {
-  for (size_t i = 0; i < sizeof(T); ++i) {
-    buf[sizeof(T)-i-1] = static_cast<char>(val & 0xFF);
-    val >>= 8;
-  }
-}
-
-// Specializations to make clang happy about the (dead code) shifts above.
-template <>
-inline void ReadBigEndian<uint8_t>(const char buf[], uint8_t* out) {
-  *out = buf[0];
-}
-
-template <>
-inline void WriteBigEndian<uint8_t>(char buf[], uint8_t val) {
-  buf[0] = static_cast<char>(val);
-}
-
-// Allows reading integers in network order (big endian) while iterating over
-// an underlying buffer. All the reading functions advance the internal pointer.
-class BASE_EXPORT BigEndianReader {
- public:
-  BigEndianReader(const char* buf, size_t len);
-
-  const char* ptr() const { return ptr_; }
-  int remaining() const { return end_ - ptr_; }
-
-  bool Skip(size_t len);
-  bool ReadBytes(void* out, size_t len);
-  // Creates a StringPiece in |out| that points to the underlying buffer.
-  bool ReadPiece(base::StringPiece* out, size_t len);
-  bool ReadU8(uint8_t* value);
-  bool ReadU16(uint16_t* value);
-  bool ReadU32(uint32_t* value);
-  bool ReadU64(uint64_t* value);
-
- private:
-  // Hidden to promote type safety.
-  template<typename T>
-  bool Read(T* v);
-
-  const char* ptr_;
-  const char* end_;
-};
-
-// Allows writing integers in network order (big endian) while iterating over
-// an underlying buffer. All the writing functions advance the internal pointer.
-class BASE_EXPORT BigEndianWriter {
- public:
-  BigEndianWriter(char* buf, size_t len);
-
-  char* ptr() const { return ptr_; }
-  int remaining() const { return end_ - ptr_; }
-
-  bool Skip(size_t len);
-  bool WriteBytes(const void* buf, size_t len);
-  bool WriteU8(uint8_t value);
-  bool WriteU16(uint16_t value);
-  bool WriteU32(uint32_t value);
-  bool WriteU64(uint64_t value);
-
- private:
-  // Hidden to promote type safety.
-  template<typename T>
-  bool Write(T v);
-
-  char* ptr_;
-  char* end_;
-};
-
-}  // namespace base
-
-#endif  // BASE_BIG_ENDIAN_H_
diff --git a/base/files/file_posix.cc b/base/files/file_posix.cc
index 9f6ae16..b7a3e9d 100644
--- a/base/files/file_posix.cc
+++ b/base/files/file_posix.cc
@@ -16,10 +16,6 @@
 #include "base/threading/thread_restrictions.h"
 #include "build_config.h"
 
-#if defined(OS_ANDROID)
-#include "base/os_compat_android.h"
-#endif
-
 namespace base {
 
 // Make sure our Whence mappings match the system headers.
diff --git a/base/files/file_util_posix.cc b/base/files/file_util_posix.cc
index 37fb015..1892baf 100644
--- a/base/files/file_util_posix.cc
+++ b/base/files/file_util_posix.cc
@@ -49,11 +49,6 @@
 #include "base/mac/foundation_util.h"
 #endif
 
-#if defined(OS_ANDROID)
-#include "base/android/content_uri_utils.h"
-#include "base/os_compat_android.h"
-#endif
-
 #if !defined(OS_IOS)
 #include <grp.h>
 #endif
diff --git a/base/os_compat_nacl.cc b/base/os_compat_nacl.cc
deleted file mode 100644
index 58fe93e..0000000
--- a/base/os_compat_nacl.cc
+++ /dev/null
@@ -1,30 +0,0 @@
-// Copyright (c) 2012 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.
-
-#include "base/os_compat_nacl.h"
-
-#include <stdlib.h>
-#include <time.h>
-
-#if !defined (__GLIBC__)
-
-extern "C" {
-// Native Client has no timegm().
-time_t timegm(struct tm* tm) {
-  time_t ret;
-  char* tz;
-  tz = getenv("TZ");
-  setenv("TZ", "", 1);
-  tzset();
-  ret = mktime(tm);
-  if (tz)
-    setenv("TZ", tz, 1);
-  else
-    unsetenv("TZ");
-  tzset();
-  return ret;
-}
-}  // extern "C"
-
-#endif  // !defined (__GLIBC__)
diff --git a/base/os_compat_nacl.h b/base/os_compat_nacl.h
deleted file mode 100644
index 13e0e3f..0000000
--- a/base/os_compat_nacl.h
+++ /dev/null
@@ -1,16 +0,0 @@
-// Copyright (c) 2012 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.
-
-#ifndef BASE_OS_COMPAT_NACL_H_
-#define BASE_OS_COMPAT_NACL_H_
-
-#include <sys/types.h>
-
-#if !defined (__GLIBC__)
-// NaCl has no timegm().
-extern "C" time_t timegm(struct tm* const t);
-#endif  // !defined (__GLIBC__)
-
-#endif  // BASE_OS_COMPAT_NACL_H_
-
diff --git a/base/time/time_exploded_posix.cc b/base/time/time_exploded_posix.cc
index ad95167..26eaed9 100644
--- a/base/time/time_exploded_posix.cc
+++ b/base/time/time_exploded_posix.cc
@@ -18,12 +18,6 @@
 #include "base/synchronization/lock.h"
 #include "build_config.h"
 
-#if defined(OS_ANDROID)
-#include "base/os_compat_android.h"
-#elif defined(OS_NACL)
-#include "base/os_compat_nacl.h"
-#endif
-
 #if defined(OS_MACOSX)
 static_assert(sizeof(time_t) >= 8, "Y2038 problem!");
 #endif
diff --git a/tools/gn/command_gen.cc b/tools/gn/command_gen.cc
index ca65877..44bf922 100644
--- a/tools/gn/command_gen.cc
+++ b/tools/gn/command_gen.cc
@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "base/atomicops.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/strings/string_number_conversions.h"