Move control of updating toolchain into src/

build/gyp_chromium

Index: build/gyp_chromium
diff --git a/build/gyp_chromium b/build/gyp_chromium
index c1de890e6721580b5fa19206622628ef70674fa5..2a9d0601e32b6266e36bf4b86206ad5b5a174cd4 100755
--- a/build/gyp_chromium
+++ b/build/gyp_chromium
@@ -330,6 +330,14 @@ def RunGN(vars_dict):
   return subprocess.call(args) == 0
 
 
+def GetDesiredVsToolchainHashes():
+  """Load a list of SHA1s corresponding to the toolchains that we want installed
+  to build with."""
+  sha1path = os.path.join(script_dir, 'toolchain_vs2013.hash')
+  with open(sha1path, 'rb') as f:
+    return f.read().strip().splitlines()
+
+
 def CopyVsRuntimeDlls(output_dir, runtime_dirs):
   """Copies the VS runtime DLLs from the given |runtime_dirs| to the output
   directory so that even if not system-installed, built binaries are likely to
@@ -438,15 +446,28 @@ if __name__ == '__main__':
       not 'OS=ios' in os.environ.get('GYP_DEFINES', []):
     os.environ['GYP_GENERATORS'] = 'ninja'
 
-  # If on windows, and the automatic toolchain has been installed by
-  # depot_tools, then use it.
+  # If on Windows, request that depot_tools install/update the automatic
+  # toolchain, and then use it (unless opted-out).
   vs2013_runtime_dll_dirs = None
-  # If MSVS_VERSION is explicitly specified to be something other than 2013,
-  # don't use the automatic toolchain, as it currently only supports VS2013.
-  msvs_version = os.environ.get('GYP_MSVS_VERSION', '2013')
-  if sys.platform in ('win32', 'cygwin') and msvs_version.startswith('2013'):
+  depot_tools_win_toolchain = \
+      bool(int(os.environ.get('DEPOT_TOOLS_WIN_TOOLCHAIN', '1')))
+  if sys.platform in ('win32', 'cygwin') and depot_tools_win_toolchain:
     import find_depot_tools
     depot_tools_path = find_depot_tools.add_depot_tools_to_path()
+    get_toolchain_args = [
+        sys.executable,
+        os.path.join(depot_tools_path,
+                     'win_toolchain',
+                     'get_toolchain_if_necessary.py'),
+    ]
+    get_toolchain_args.extend(GetDesiredVsToolchainHashes())

[iannucci, 2014/02/21 23:56:14]

the + operator works too :P

[scottmg, 2014/02/22 00:10:43]

maruel always asks for + -> extend/append. Geez, Code Reviews! 9_9

+    subprocess.check_call(get_toolchain_args)
+
+    # TODO(scottmg): This should point at vs2013_files/<sha1> so that we can
+    # have multiple versions concurrently. This is slightly complicated at the
+    # moment because the downloader script doesn't know the SHA1 of the
+    # toolchain that it's downloading, so only supports having one 'installed'
+    # at a time.

[iannucci, 2014/02/21 23:56:14]

We should probably have the depot tools thing print out the path to the
installed tools, or, better, the path to the batch file / json file with the env
vars.

[scottmg, 2014/02/22 00:10:43]

This seems better, except it's a somewhat long process, so I'd like to have it
send some output to stdout for the user's benefit. It could write a file ...
somewhere?

     toolchain = os.path.normpath(os.path.join(
         depot_tools_path, 'win_toolchain', 'vs2013_files'))
     version_file = os.path.join(toolchain, '.version')