Add a snapshot of flutter/engine/src/build to our sdk

build/build_config.h

Index: build/build_config.h
diff --git a/build/build_config.h b/build/build_config.h
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+// 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
+//  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
+#define TOOLKIT_VIEWS 1
+#elif defined(__FreeBSD__)
+#define OS_FREEBSD 1
+#elif defined(__OpenBSD__)
+#define OS_OPENBSD 1
+#elif defined(__sun)
+#define OS_SOLARIS 1
+#elif defined(__QNXNTO__)
+#define OS_QNX 1
+#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_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_OPENBSD) || defined(OS_SOLARIS) || defined(OS_ANDROID) ||  \
+    defined(OS_NACL) || defined(OS_QNX)
+#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(__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__)
+#define ARCH_CPU_32_BITS 1
+#define ARCH_CPU_LITTLE_ENDIAN 1
+#elif defined(__MIPSEL__)
+#if defined(__LP64__)
+#define ARCH_CPU_MIPS64_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_