SDK: Add a Makefile to build the C++ stuff.

sdk_build/data/cpp/cpp.sdk

 # Copyright 2016 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 contains steps for "building" a C/C++ SDK. It is processed by
 # //mojo/sdk_build/build_sdk.py.
-# TODO(vtl): This isn't done yet.
+# TODO(vtl): This isn't done yet. (Or is it?)
 
 import re
 
 EXCLUDE_FILES=[".*", "*.gn", "*.gni", "PRESUBMIT.py", "*_win.*"]
 EXCLUDE_PATHS=["*/tests/*"]
 
 WriteFile("MOJO_SDK_VERSION", "%s\n" % GitGetRevision())
 
 CopyDir("mojo/public",
         "mojo/public",
@@ skipping 41 matching lines @@
 CopyDir("mojo/public/python/dummy_mojo_system",
         "mojo/public/python/dummy_mojo_system",
         recursive=True)
 CopyDir("mojo/public/python/mojo_bindings",
         "mojo/public/python/mojo_bindings",
         recursive=True)
 
 # Scripts to download binaries.
 CopyFiles(["sdk_build/data/common/download_file_from_google_storage.py",
            "sdk_build/data/common/download_mojom_tool.sh",
-           "sdk_build/data/cpp/download_clang.sh"],
+           "sdk_build/data/cpp/download_clang.sh",
+           "sdk_build/data/cpp/setup.sh"],
           "mojo_sdk_setup")
 
 # Figure out the version of clang, and include that. (This is a little janky,
 # but it's how we roll.)
 clang_update_script = ReadFile("tools/clang/scripts/update.sh")
 clang_revision = re.search(r"^CLANG_REVISION=(\d+)$",
                            clang_update_script,
                            re.MULTILINE).group(1)
 clang_sub_revision = re.search(r"^CLANG_SUB_REVISION=(\d+)$",
                                clang_update_script,
                                re.MULTILINE).group(1)
 WriteFile("mojo_sdk_setup/data/CLANG_VERSION",
           "%s-%s\n" % (clang_revision, clang_sub_revision))
 
 # Seed an example.
 CopyDir("examples/hello_mojo",
         "examples/hello_mojo",
         recursive=True,
         exclude_file_patterns=EXCLUDE_FILES)
+
+# Put in a simple example Makefile (in the root directory).
+CopyFiles("sdk_build/data/cpp/Makefile", "")