Use depot_tools toolchain, remove now unneeded code, fix not including path to win sdk tools

build/toolchain/win/setup_toolchain.py

Index: build/toolchain/win/setup_toolchain.py
diff --git a/build/toolchain/win/setup_toolchain.py b/build/toolchain/win/setup_toolchain.py
index bceafd121be44b6c0c2271ea8c40462937493fd7..19f73b4d19e06660bcf6877c94b2d7579a36c820 100644
--- a/build/toolchain/win/setup_toolchain.py
+++ b/build/toolchain/win/setup_toolchain.py
@@ -23,17 +23,18 @@ def ExtractImportantEnvironment():
   """Extracts environment variables required for the toolchain from the
   current environment."""
   envvars_to_save = (
-      'goma_.*', # TODO(scottmg): This is ugly, but needed for goma.
-      'Path',
-      'PATHEXT',
-      'SystemRoot',
-      'TEMP',
-      'TMP',
+      'goma_.*',  # TODO(scottmg): This is ugly, but needed for goma.
+      'path',
+      'pathext',
+      'systemroot',
+      'temp',
+      'tmp',
       )
   result = {}
   for envvar in envvars_to_save:
     if envvar in os.environ:
-      if envvar == 'Path':
+      envvar = envvar.lower()
+      if envvar == 'path':
         # Our own rules (for running gyp-win-tool) and other actions in
         # Chromium rely on python being in the path. Add the path to this
         # python here so that if it's not in the path when ninja is run
@@ -74,11 +75,13 @@ def CopyTool(source_path):
                              '# Generated by setup_toolchain.py do not edit.\n']
                             + tool_source[1:]))
 
-if len(sys.argv) != 3:
-  print 'Usage setup_toolchain.py <visual studio path> <win tool path>'
+if len(sys.argv) != 4:
+  print('Usage setup_toolchain.py '
+        '<visual studio path> <win tool path> <win sdk path>')
   sys.exit(2)
 vs_path = sys.argv[1]
 tool_source = sys.argv[2]
+win_sdk_path = sys.argv[3]
 
 CopyTool(tool_source)
 
@@ -86,14 +89,18 @@ important_env_vars = ExtractImportantEnvironment()
 path = important_env_vars["PATH"].split(";")
 
 # Add 32-bit compiler path to the beginning and write the block.
-path32 = [os.path.join(vs_path, "VC\\BIN")] + path
+path32 = [os.path.join(vs_path, "VC\\BIN")] + \
+         [os.path.join(win_sdk_path, "bin\\x86")] + \
+         path
 important_env_vars["PATH"] = ";".join(path32)
 environ = FormatAsEnvironmentBlock(important_env_vars)
 with open('environment.x86', 'wb') as env_file:
   env_file.write(environ)
 
 # Add 64-bit compiler path to the beginning and write the block.
-path64 = [os.path.join(vs_path, "VC\\BIN\\amd64")] + path
+path64 = [os.path.join(vs_path, "VC\\BIN\\amd64")] + \
+         [os.path.join(win_sdk_path, "bin\\x64")] + \
+         path
 important_env_vars["PATH"] = ";".join(path64)
 environ = FormatAsEnvironmentBlock(important_env_vars)
 with open('environment.x64', 'wb') as env_file: