Use find_depot_tools.py and vs_toolchain.py from chromium/src/build/

DEPS

 # DEPS files look like -*- Python -*-
 
 vars = {
   # These revisions are slices of the chromium repository.
   # Because they come from separate sub-slices, their hashes do not match at
   # equivalent revisions. When updating them, use the roll-dep script
   # to move them to equivalent revisions. Additionally, because not all
   # directories contain commits at each revision, you will need to select
   # revisions at latest revision up to a high watermark from each slice.
   # Document the high watermark here:
@@ skipping 125 matching lines @@
   # Cleanup any stale package_version files.
   {
     "pattern": ".",
     "action": ["python",
                "native_client/build/package_version/package_version.py",
                "cleanup",
     ],
   },
   {
     # Update the Windows toolchain if necessary.
-    "name": "win_toolchain",
-    "pattern": ".",
-    "action": ["python", "native_client/build/vs_toolchain.py", "update"],
+    'name': 'win_toolchain',
+    'pattern': '.',
+    'action': ['python', 'build/vs_toolchain.py', 'update'],
   },
   # Pull binutils for linux, enabled debug fission for faster linking /
   # debugging when used with clang on Ubuntu Precise.
   # https://code.google.com/p/chromium/issues/detail?id=352046
   {
     'name': 'binutils',
     'pattern': 'third_party/binutils',
     'action': [
         'python',
         'third_party/binutils/download.py',
@@ skipping 79 matching lines @@
                 "--bucket", "chromium-clang-format",
                 "-s", "buildtools/linux64/clang-format.sha1",
     ],
   },
 ]
 
 include_rules = [
   "+native_client/src/include",
   "+gtest",
 ]