Specify default Python 2 command on Windows since shebang lines don't work

Create the directories pointed to by TEMP and TMP environment variables

Author: Eloston

BUILDING.md

@@ -67,8 +67,6 @@ Make sure all of the following are in the `PATH`:
 * gperf as `gperf`
 * bison as `bison`
 
-Also, ensure that `TEMP` and `TMP` environment variables point to existing directories.
-
 See `build.py` for more on customizing the build environment or process.
 
 ### Build

buildlib.py

@@ -702,6 +702,7 @@ class WindowsBuilder(Builder):
 
     syzygy_archive = None
     patch_command = ["patch", "-p1"]
+    python2_command = "python"
     use_depot_tools_toolchain = False
 
     @staticmethod
@@ -769,6 +770,13 @@ def generate_build_configuration(self):
             append_environ = {"DEPOT_TOOLS_WIN_TOOLCHAIN": "0"}
         self._gyp_generate_ninja(self._get_gyp_flags(), append_environ)
 
+    def build(self):
+        # Try to make temporary directories so ninja won't fail
+        os.makedirs(os.environ["TEMP"], exist_ok=True)
+        os.makedirs(os.environ["TMP"], exist_ok=True)
+
+        super(WindowsBuilder, self).build()
+
     def generate_package(self):
         # Derived from chrome/tools/build/make_zip.py
         # Hardcoded to only include files with buildtype "dev" and "official", and files for 32bit