diff --git a/third_party/base/allocator/partition_allocator/address_space_randomization.cc b/third_party/base/allocator/partition_allocator/address_space_randomization.cc
index 08f22be..d16970a 100644
--- a/third_party/base/allocator/partition_allocator/address_space_randomization.cc
+++ b/third_party/base/allocator/partition_allocator/address_space_randomization.cc
@@ -4,9 +4,9 @@
 
 #include "third_party/base/allocator/partition_allocator/address_space_randomization.h"
 
+#include "build/build_config.h"
 #include "third_party/base/allocator/partition_allocator/page_allocator.h"
 #include "third_party/base/allocator/partition_allocator/spin_lock.h"
-#include "third_party/build/build_config.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
diff --git a/third_party/base/allocator/partition_allocator/page_allocator.cc b/third_party/base/allocator/partition_allocator/page_allocator.cc
index abe159b..0869bdb 100644
--- a/third_party/base/allocator/partition_allocator/page_allocator.cc
+++ b/third_party/base/allocator/partition_allocator/page_allocator.cc
@@ -8,10 +8,10 @@
 
 #include <atomic>
 
+#include "build/build_config.h"
 #include "third_party/base/allocator/partition_allocator/address_space_randomization.h"
 #include "third_party/base/base_export.h"
 #include "third_party/base/logging.h"
-#include "third_party/build/build_config.h"
 
 #if defined(OS_POSIX)
 
diff --git a/third_party/base/allocator/partition_allocator/page_allocator.h b/third_party/base/allocator/partition_allocator/page_allocator.h
index aee2532..bf9c098 100644
--- a/third_party/base/allocator/partition_allocator/page_allocator.h
+++ b/third_party/base/allocator/partition_allocator/page_allocator.h
@@ -9,9 +9,9 @@
 
 #include <cstddef>
 
+#include "build/build_config.h"
 #include "third_party/base/base_export.h"
 #include "third_party/base/compiler_specific.h"
-#include "third_party/build/build_config.h"
 
 namespace pdfium {
 namespace base {
diff --git a/third_party/base/allocator/partition_allocator/partition_alloc.h b/third_party/base/allocator/partition_allocator/partition_alloc.h
index 7e8415c..87db329 100644
--- a/third_party/base/allocator/partition_allocator/partition_alloc.h
+++ b/third_party/base/allocator/partition_allocator/partition_alloc.h
@@ -62,13 +62,13 @@
 #include <limits.h>
 #include <string.h>
 
+#include "build/build_config.h"
 #include "third_party/base/allocator/partition_allocator/page_allocator.h"
 #include "third_party/base/allocator/partition_allocator/spin_lock.h"
 #include "third_party/base/bits.h"
 #include "third_party/base/compiler_specific.h"
 #include "third_party/base/logging.h"
 #include "third_party/base/sys_byteorder.h"
-#include "third_party/build/build_config.h"
 
 #if defined(MEMORY_TOOL_REPLACES_ALLOCATOR)
 #include <stdlib.h>
diff --git a/third_party/base/sys_byteorder.h b/third_party/base/sys_byteorder.h
index 593abe1..db8cc16 100644
--- a/third_party/base/sys_byteorder.h
+++ b/third_party/base/sys_byteorder.h
@@ -13,8 +13,8 @@
 
 #include <stdint.h>
 
+#include "build/build_config.h"
 #include "third_party/base/logging.h"
-#include "third_party/build/build_config.h"
 
 #if defined(COMPILER_MSVC)
 #include <stdlib.h>
diff --git a/third_party/base/template_util.h b/third_party/base/template_util.h
index b246322..0fed0cc 100644
--- a/third_party/base/template_util.h
+++ b/third_party/base/template_util.h
@@ -10,7 +10,7 @@
 #include <type_traits>
 #include <utility>
 
-#include "third_party/build/build_config.h"
+#include "build/build_config.h"
 
 // This hacks around libstdc++ 4.6 missing stuff in type_traits, while we need
 // to support it.
diff --git a/third_party/build/build_config.h b/third_party/build/build_config.h
deleted file mode 100644
index e59b7b9..0000000
--- a/third_party/build/build_config.h
+++ /dev/null
@@ -1,197 +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.
-
-// This file adds defines about the platform we're currently building on.
-//  Operating System:
-//    OS_WIN / OS_MACOSX / OS_LINUX / OS_POSIX (MACOSX or LINUX) /
-//    OS_NACL (NACL_SFI or NACL_NONSFI) / OS_NACL_SFI / OS_NACL_NONSFI
-//    OS_CHROMEOS is set by the build system
-//  Compiler:
-//    COMPILER_MSVC / COMPILER_GCC
-//  Processor:
-//    ARCH_CPU_X86 / ARCH_CPU_X86_64 / ARCH_CPU_X86_FAMILY (X86 or X86_64)
-//    ARCH_CPU_32_BITS / ARCH_CPU_64_BITS
-
-#ifndef BUILD_BUILD_CONFIG_H_
-#define BUILD_BUILD_CONFIG_H_
-
-// A set of macros to use for platform detection.
-#if defined(__native_client__)
-// __native_client__ must be first, so that other OS_ defines are not set.
-#define OS_NACL 1
-// OS_NACL comes in two sandboxing technology flavors, SFI or Non-SFI.
-// PNaCl toolchain defines __native_client_nonsfi__ macro in Non-SFI build
-// mode, while it does not in SFI build mode.
-#if defined(__native_client_nonsfi__)
-#define OS_NACL_NONSFI
-#else
-#define OS_NACL_SFI
-#endif
-#elif defined(ANDROID)
-#define OS_ANDROID 1
-#elif defined(__APPLE__)
-// only include TargetConditions after testing ANDROID as some android builds
-// on mac don't have this header available and it's not needed unless the target
-// is really mac/ios.
-#include <TargetConditionals.h>
-#define OS_MACOSX 1
-#if defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE
-#define OS_IOS 1
-#endif  // defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE
-#elif defined(__linux__)
-#define OS_LINUX 1
-// include a system header to pull in features.h for glibc/uclibc macros.
-#include <unistd.h>
-#if defined(__GLIBC__) && !defined(__UCLIBC__)
-// we really are using glibc, not uClibc pretending to be glibc
-#define LIBC_GLIBC 1
-#endif
-#elif defined(_WIN32)
-#define OS_WIN 1
-#elif defined(__FreeBSD__)
-#define OS_FREEBSD 1
-#elif defined(__NetBSD__)
-#define OS_NETBSD 1
-#elif defined(__OpenBSD__)
-#define OS_OPENBSD 1
-#elif defined(__sun)
-#define OS_SOLARIS 1
-#elif defined(__QNXNTO__)
-#define OS_QNX 1
-#elif defined(__asmjs__)
-#define OS_ASMJS
-#else
-#error Please add support for your platform in build/build_config.h
-#endif
-
-#if defined(USE_OPENSSL_CERTS) && defined(USE_NSS_CERTS)
-#error Cannot use both OpenSSL and NSS for certificates
-#endif
-
-// For access to standard BSD features, use OS_BSD instead of a
-// more specific macro.
-#if defined(OS_FREEBSD) || defined(OS_NETBSD) || defined(OS_OPENBSD)
-#define OS_BSD 1
-#endif
-
-// For access to standard POSIXish features, use OS_POSIX instead of a
-// more specific macro.
-#if defined(OS_MACOSX) || defined(OS_LINUX) || defined(OS_FREEBSD) ||    \
-    defined(OS_NETBSD) || defined(OS_OPENBSD) || defined(OS_SOLARIS) ||  \
-    defined(OS_ANDROID) || defined(OS_OPENBSD) || defined(OS_SOLARIS) || \
-    defined(OS_ANDROID) || defined(OS_NACL) || defined(OS_QNX) ||        \
-    defined(OS_ASMJS)
-#define OS_POSIX 1
-#endif
-
-// Use tcmalloc
-#if (defined(OS_WIN) || defined(OS_LINUX) || defined(OS_ANDROID)) && \
-    !defined(NO_TCMALLOC)
-#define USE_TCMALLOC 1
-#endif
-
-// Compiler detection.
-#if defined(__GNUC__)
-#define COMPILER_GCC 1
-#elif defined(_MSC_VER)
-#define COMPILER_MSVC 1
-#else
-#error Please add support for your compiler in build/build_config.h
-#endif
-
-// Processor architecture detection.  For more info on what's defined, see:
-//   http://msdn.microsoft.com/en-us/library/b0084kay.aspx
-//   http://www.agner.org/optimize/calling_conventions.pdf
-//   or with gcc, run: "echo | gcc -E -dM -"
-#if defined(_M_X64) || defined(__x86_64__)
-#define ARCH_CPU_X86_FAMILY 1
-#define ARCH_CPU_X86_64 1
-#define ARCH_CPU_64_BITS 1
-#define ARCH_CPU_LITTLE_ENDIAN 1
-#elif defined(_M_IX86) || defined(__i386__)
-#define ARCH_CPU_X86_FAMILY 1
-#define ARCH_CPU_X86 1
-#define ARCH_CPU_32_BITS 1
-#define ARCH_CPU_LITTLE_ENDIAN 1
-#elif defined(__s390x__)
-#define ARCH_CPU_S390_FAMILY 1
-#define ARCH_CPU_S390X 1
-#define ARCH_CPU_64_BITS 1
-#define ARCH_CPU_BIG_ENDIAN 1
-#elif defined(__s390__)
-#define ARCH_CPU_S390_FAMILY 1
-#define ARCH_CPU_S390 1
-#define ARCH_CPU_31_BITS 1
-#define ARCH_CPU_BIG_ENDIAN 1
-#elif defined(__PPC64__) && defined(__BIG_ENDIAN__)
-#define ARCH_CPU_PPC64_FAMILY 1
-#define ARCH_CPU_PPC64 1
-#define ARCH_CPU_64_BITS 1
-#define ARCH_CPU_BIG_ENDIAN 1
-#elif defined(__PPC64__) && defined(__LITTLE_ENDIAN__)
-#define ARCH_CPU_PPC64_FAMILY 1
-#define ARCH_CPU_PPC64 1
-#define ARCH_CPU_64_BITS 1
-#define ARCH_CPU_LITTLE_ENDIAN 1
-#elif defined(__PPC__)
-#define ARCH_CPU_PPC_FAMILY 1
-#define ARCH_CPU_PPC 1
-#define ARCH_CPU_32_BITS 1
-#define ARCH_CPU_BIG_ENDIAN 1
-#elif defined(__ARMEL__)
-#define ARCH_CPU_ARM_FAMILY 1
-#define ARCH_CPU_ARMEL 1
-#define ARCH_CPU_32_BITS 1
-#define ARCH_CPU_LITTLE_ENDIAN 1
-#elif defined(__aarch64__)
-#define ARCH_CPU_ARM_FAMILY 1
-#define ARCH_CPU_ARM64 1
-#define ARCH_CPU_64_BITS 1
-#define ARCH_CPU_LITTLE_ENDIAN 1
-#elif defined(__pnacl__) || defined(__asmjs__)
-#define ARCH_CPU_32_BITS 1
-#define ARCH_CPU_LITTLE_ENDIAN 1
-#elif defined(__MIPSEL__)
-#if defined(__LP64__)
-#define ARCH_CPU_MIPS_FAMILY 1
-#define ARCH_CPU_MIPS64EL 1
-#define ARCH_CPU_64_BITS 1
-#define ARCH_CPU_LITTLE_ENDIAN 1
-#else
-#define ARCH_CPU_MIPS_FAMILY 1
-#define ARCH_CPU_MIPSEL 1
-#define ARCH_CPU_32_BITS 1
-#define ARCH_CPU_LITTLE_ENDIAN 1
-#endif
-#else
-#error Please add support for your architecture in build/build_config.h
-#endif
-
-// Type detection for wchar_t.
-#if defined(OS_WIN)
-#define WCHAR_T_IS_UTF16
-#elif defined(OS_POSIX) && defined(COMPILER_GCC) && defined(__WCHAR_MAX__) && \
-    (__WCHAR_MAX__ == 0x7fffffff || __WCHAR_MAX__ == 0xffffffff)
-#define WCHAR_T_IS_UTF32
-#elif defined(OS_POSIX) && defined(COMPILER_GCC) && defined(__WCHAR_MAX__) && \
-    (__WCHAR_MAX__ == 0x7fff || __WCHAR_MAX__ == 0xffff)
-// On Posix, we'll detect short wchar_t, but projects aren't guaranteed to
-// compile in this mode (in particular, Chrome doesn't). This is intended for
-// other projects using base who manage their own dependencies and make sure
-// short wchar works for them.
-#define WCHAR_T_IS_UTF16
-#else
-#error Please add support for your compiler in build/build_config.h
-#endif
-
-#if defined(OS_ANDROID)
-// The compiler thinks std::string::const_iterator and "const char*" are
-// equivalent types.
-#define STD_STRING_ITERATOR_IS_CHAR_POINTER
-// The compiler thinks base::string16::const_iterator and "char16*" are
-// equivalent types.
-#define BASE_STRING16_ITERATOR_IS_CHAR16_POINTER
-#endif
-
-#endif  // BUILD_BUILD_CONFIG_H_