GN android flavor windows support

GN is a .bat, fetch-gn is a Python script, ninja is an .exe.
Just the same stuff gn_flavor does in the same way.

TBR=borenet@google.com

BUG=skia:

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4321

Change-Id: I89ce3711a6dea46d32fe03c5719ef635defe54f7
Reviewed-on: https://skia-review.googlesource.com/4321
Commit-Queue: Mike Klein <mtklein@chromium.org>
Reviewed-by: Mike Klein <mtklein@chromium.org>

infra/bots/recipe_modules/flavor/gn_android_flavor.py

@@ -25,13 +25,21 @@ class GNAndroidFlavorUtils(default_flavor.DefaultFlavorUtils):
         svg_dir       = _data_dir + 'svgs',
         tmp_dir       = _data_dir)
 
-  def _run(self, title, *cmd, **kwargs):
+  def _strip_environment(self):
     self.m.vars.default_env = {k: v for (k,v)
                                in self.m.vars.default_env.iteritems()
                                if k in ['PATH']}
+
+  def _run(self, title, *cmd, **kwargs):
+    self._strip_environment()
     return self.m.run(self.m.step, title, cmd=list(cmd),
                       cwd=self.m.vars.skia_dir, **kwargs)
 
+  def _py(self, title, script, infra_step=True):
+    self._strip_environment()
+    return self.m.run(self.m.python, title, script=script,
+                      cwd=self.m.vars.skia_dir, env=None, infra_step=infra_step)
+
   def _adb(self, title, *cmd, **kwargs):
     self._ever_ran_adb = True
     # The only non-infra adb steps (dm / nanobench) happen to not use _adb().
@@ -76,10 +84,12 @@ class GNAndroidFlavorUtils(default_flavor.DefaultFlavorUtils):
 
     gn_args = ' '.join('%s=%s' % (k,v) for (k,v) in sorted(args.iteritems()))
 
-    self._run('fetch-gn', self.m.vars.skia_dir.join('bin', 'fetch-gn'),
-              infra_step=True)
-    self._run('gn gen', 'gn', 'gen', self.out_dir, '--args=' + gn_args)
-    self._run('ninja', 'ninja', '-C', self.out_dir)
+    gn    = 'gn.bat'    if 'Win' in os else 'gn'
+    ninja = 'ninja.exe' if 'Win' in os else 'ninja'
+
+    self._py('fetch-gn', self.m.vars.skia_dir.join('bin', 'fetch-gn'))
+    self._run('gn gen', gn, 'gen', self.out_dir, '--args=' + gn_args)
+    self._run('ninja', ninja, '-C', self.out_dir)
 
   def install(self):
     self._adb('mkdir ' + self.device_dirs.resource_dir,

infra/bots/recipes/swarm_compile.expected/Build-Mac-Clang-mipsel-Debug-GN_Android.json

@@ -77,6 +77,8 @@
   },
   {
     "cmd": [
+      "python",
+      "-u",
       "[CUSTOM_/_B_WORK]/skia/bin/fetch-gn"
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",

infra/bots/recipes/swarm_compile.expected/Build-Ubuntu-Clang-arm64-Debug-GN_Android-Trybot.json

@@ -83,6 +83,8 @@
   },
   {
     "cmd": [
+      "python",
+      "-u",
       "[CUSTOM_/_B_WORK]/skia/bin/fetch-gn"
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",

infra/bots/recipes/swarm_compile.expected/Build-Ubuntu-Clang-arm64-Debug-GN_Android_FrameworkDefs.json

@@ -77,6 +77,8 @@
   },
   {
     "cmd": [
+      "python",
+      "-u",
       "[CUSTOM_/_B_WORK]/skia/bin/fetch-gn"
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",

infra/bots/recipes/swarm_compile.expected/Build-Ubuntu-Clang-arm64-Release-GN_Android.json

@@ -77,6 +77,8 @@
   },
   {
     "cmd": [
+      "python",
+      "-u",
       "[CUSTOM_/_B_WORK]/skia/bin/fetch-gn"
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",

infra/bots/recipes/swarm_compile.expected/Build-Ubuntu-Clang-arm64-Release-GN_Android_Vulkan.json

@@ -77,6 +77,8 @@
   },
   {
     "cmd": [
+      "python",
+      "-u",
       "[CUSTOM_/_B_WORK]/skia/bin/fetch-gn"
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",

infra/bots/recipes/swarm_compile.expected/Build-Win-Clang-arm64-Release-GN_Android.json

@@ -77,6 +77,8 @@
   },
   {
     "cmd": [
+      "python",
+      "-u",
       "[CUSTOM_C:\\_B_WORK]\\skia\\bin\\fetch-gn"
     ],
     "cwd": "[CUSTOM_C:\\_B_WORK]\\skia",
@@ -87,7 +89,7 @@
   },
   {
     "cmd": [
-      "gn",
+      "gn.bat",
       "gen",
       "[CUSTOM_C:\\_B_WORK]\\skia\\out\\Build-Win-Clang-arm64-Release-GN_Android\\Release",
       "--args=is_debug=false ndk=\"[SLAVE_BUILD]\\n\" target_cpu=\"arm64\""
@@ -100,7 +102,7 @@
   },
   {
     "cmd": [
-      "ninja",
+      "ninja.exe",
       "-C",
       "[CUSTOM_C:\\_B_WORK]\\skia\\out\\Build-Win-Clang-arm64-Release-GN_Android\\Release"
     ],