Add FreeBSD as a supported platform using ninja.

build/landmine_utils.py

Index: build/landmine_utils.py
diff --git a/build/landmine_utils.py b/build/landmine_utils.py
index 46086fa83e069721c3d69e8124dc468f4e7da4d9..aa11bb8a85c477f6010a64b94a61c44e4d581623 100644
--- a/build/landmine_utils.py
+++ b/build/landmine_utils.py
@@ -42,6 +42,11 @@ def IsMac():
 
 
 @memoize()
+def IsFreeBSD():
+  return sys.platform.startswith('freebsd')
+
+
+@memoize()
 def gyp_defines():
   """Parses and returns GYP_DEFINES env var as a dictionary."""
   return dict(arg.split('=', 1)
@@ -68,7 +73,7 @@ def distributor():
 def platform():
   """
   Returns a string representing the platform this build is targetted for.
-  Possible values: 'win', 'mac', 'linux', 'ios', 'android'
+  Possible values: 'win', 'mac', 'linux', 'ios', 'android', 'freebsd'
   """
   if 'OS' in gyp_defines():
     if 'android' in gyp_defines()['OS']:
@@ -79,6 +84,8 @@ def platform():
     return 'win'
   elif IsLinux():
     return 'linux'
+  elif IsFreeBSD():
+    return 'freebsd'
   else:
     return 'mac'
 
@@ -110,5 +117,7 @@ def builder():
       return 'ninja'
     elif IsMac():
       return 'ninja'
+    elif IsFreeBSD():
+      return 'ninja'
     else:
       assert False, 'Don\'t know what builder we\'re using!'