Revert of Simplify landmines code a bit now that all branches of all platforms...

Revert of Simplify landmines code a bit now that all branches of all platforms are on ninja (patchset #2 id:20001 of https://codereview.chromium.org/2071463002/ )

Reason for revert:
I just synced on Windows and this is giving me:

________ running 'D:\depot_tools\python276_bin\python.exe src/build/landmines.py
' in 'D:\src\src1'
Traceback (most recent call last):
  File "D:\src\src1\src\build\get_landmines.py", line 16, in <module>
    builder = landmine_utils.builder
AttributeError: 'module' object has no attribute 'builder'
Clobbering due to:
--- old_landmines       Tue Aug 12 16:34:51 2014
+++ new_landmines       Fri Jul 29 15:16:56 2016
@@ -1,17 +0,0 @@
-Compile on cc_unittests fails due to symbols removed in r185063.
-Improper dependency for create_nmf.py broke in r240802, fixed in r240860.
-Switch to VS2015 Update 2
-Need to clobber everything due to an IDL change in r154579 (blink)
-Need to clobber everything due to gen file moves in r175513 (Blink)
-Clobber to get rid of obselete test plugin after r248358
-Clobber to rebuild GN files for V8
-Clobber to get rid of stale generated mojom.h files
-Need to clobber everything due to build_nexe change in nacl r13424
-[chromium-dev] PSA: clobber build needed for IDR_INSPECTOR_* compil...
-blink_resources.grd changed: crbug.com/400860
-ninja dependency cycle: crbug.com/408192
-Clobber to fix missing NaCl gyp dependencies (crbug.com/427427).
-Another clobber for missing NaCl gyp deps (crbug.com/427427).
-Clobber to fix GN not picking up increased ID range (crbug.com/444902)
-Remove NaCl toolchains from the output dir (crbug.com/456902)
-Clobber to delete stale generated files (crbug.com/510086)

Original issue's description:
> Simplify landmines code a bit now that all branches of all platforms are on ninja
>
> BUG=none
>
> Committed: https://crrev.com/7491d14275670fad399837445b6c1e76ff498a50
> Cr-Commit-Position: refs/heads/master@{#408739}

TBR=iannucci@chromium.org,thakis@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=none

Review-Url: https://codereview.chromium.org/2198583002
Cr-Commit-Position: refs/heads/master@{#408784}

build/get_landmines.py

@@ -30,26 +30,27 @@ def print_landmines():
   # dependency problems, fix the dependency problems instead of adding a
   # landmine.
 
-  if distributor() == 'goma' and platform() == 'win32':
+  if (distributor() == 'goma' and platform() == 'win32' and
+      builder() == 'ninja'):
     print 'Need to clobber winja goma due to backend cwd cache fix.'
   if platform() == 'android':
     print 'Clobber: to handle new way of suppressing findbugs failures.'
     print 'Clobber to fix gyp not rename package name (crbug.com/457038)'
-  if platform() == 'win':
+  if platform() == 'win' and builder() == 'ninja':
     print 'Compile on cc_unittests fails due to symbols removed in r185063.'
-  if platform() == 'linux':
+  if platform() == 'linux' and builder() == 'ninja':
     print 'Builders switching from make to ninja will clobber on this.'
   if platform() == 'mac':
     print 'Switching from bundle to unbundled dylib (issue 14743002).'
   if platform() in ('win', 'mac'):
     print ('Improper dependency for create_nmf.py broke in r240802, '
            'fixed in r240860.')
-  if (platform() == 'win' and
+  if (platform() == 'win' and builder() == 'ninja' and
       gyp_msvs_version() == '2012' and
       gyp_defines().get('target_arch') == 'x64' and
       gyp_defines().get('dcheck_always_on') == '1'):
     print "Switched win x64 trybots from VS2010 to VS2012."
-  if (platform() == 'win' and
+  if (platform() == 'win' and builder() == 'ninja' and
       gyp_msvs_version().startswith('2013')):
     print "Switch to VS2013"
   if (platform() == 'win' and gyp_msvs_version().startswith('2015')):

build/landmine_utils.py

@@ -47,27 +47,27 @@ def gyp_defines():
   return dict(arg.split('=', 1)
       for arg in shlex.split(os.environ.get('GYP_DEFINES', '')))
 
-
 @memoize()
 def gyp_generator_flags():
   """Parses and returns GYP_GENERATOR_FLAGS env var as a dictionary."""
   return dict(arg.split('=', 1)
       for arg in shlex.split(os.environ.get('GYP_GENERATOR_FLAGS', '')))
 
-
 @memoize()
 def gyp_msvs_version():
   return os.environ.get('GYP_MSVS_VERSION', '')
 
-
 @memoize()
 def distributor():
   """
   Returns a string which is the distributed build engine in use (if any).
-  Possible values: 'goma', None
+  Possible values: 'goma', 'ib', ''
   """
   if 'goma' in gyp_defines():
     return 'goma'
+  elif IsWindows():
+    if 'CHROME_HEADLESS' in os.environ:
+      return 'ib' # use (win and !goma and headless) as approximation of ib
 
 
 @memoize()
@@ -87,3 +87,34 @@ def platform():
     return 'linux'
   else:
     return 'mac'
+
+
+@memoize()
+def builder():
+  """
+  Returns a string representing the build engine (not compiler) to use.
+  Possible values: 'make', 'ninja', 'xcode', 'msvs', 'scons'
+  """
+  if 'GYP_GENERATORS' in os.environ:
+    # for simplicity, only support the first explicit generator
+    generator = os.environ['GYP_GENERATORS'].split(',')[0]
+    if generator.endswith('-android'):
+      return generator.split('-')[0]
+    elif generator.endswith('-ninja'):
+      return 'ninja'
+    else:
+      return generator
+  else:
+    if platform() == 'android':
+      # Good enough for now? Do any android bots use make?
+      return 'ninja'
+    elif platform() == 'ios':
+      return 'xcode'
+    elif IsWindows():
+      return 'ninja'
+    elif IsLinux():
+      return 'ninja'
+    elif IsMac():
+      return 'ninja'
+    else:
+      assert False, 'Don\'t know what builder we\'re using!'

build/landmines.py

@@ -27,28 +27,35 @@ import clobber
 import landmine_utils
 
 
-def get_build_dir(src_dir):
+def get_build_dir(build_tool, src_dir, is_iphone=False):
   """
   Returns output directory absolute path dependent on build and targets.
   Examples:
     r'c:\b\build\slave\win\build\src\out'
     '/mnt/data/b/build/slave/linux/build/src/out'
-    '/b/build/slave/ios_rel_device/build/src/out'
+    '/b/build/slave/ios_rel_device/build/src/xcodebuild'
 
   Keep this function in sync with tools/build/scripts/slave/compile.py
   """
-  if 'CHROMIUM_OUT_DIR' in os.environ:
-    output_dir = os.environ.get('CHROMIUM_OUT_DIR').strip()
-    if not output_dir:
-      raise Error('CHROMIUM_OUT_DIR environment variable is set but blank!')
+  ret = None
+  if build_tool == 'xcode':
+    ret = os.path.join(src_dir, 'xcodebuild')
+  elif build_tool in ['make', 'ninja', 'ninja-ios']:  # TODO: Remove ninja-ios.
+    if 'CHROMIUM_OUT_DIR' in os.environ:
+      output_dir = os.environ.get('CHROMIUM_OUT_DIR').strip()
+      if not output_dir:
+        raise Error('CHROMIUM_OUT_DIR environment variable is set but blank!')
+    else:
+      output_dir = landmine_utils.gyp_generator_flags().get('output_dir', 'out')
+    ret = os.path.join(src_dir, output_dir)
   else:
-    output_dir = landmine_utils.gyp_generator_flags().get('output_dir', 'out')
-  return os.path.abspath(os.path.join(src_dir, output_dir))
+    raise NotImplementedError('Unexpected GYP_GENERATORS (%s)' % build_tool)
+  return os.path.abspath(ret)
 
 
 def clobber_if_necessary(new_landmines, src_dir):
   """Does the work of setting, planting, and triggering landmines."""
-  out_dir = get_build_dir(src_dir)
+  out_dir = get_build_dir(landmine_utils.builder(), src_dir)
   landmines_path = os.path.normpath(os.path.join(src_dir, '.landmines'))
   try:
     os.makedirs(out_dir)
@@ -122,6 +129,9 @@ def process_options():
 def main():
   options = process_options()
 
+  if landmine_utils.builder() in ('dump_dependency_json', 'eclipse'):
+    return 0
+
   gyp_environment.SetEnvironment()
 
   landmines = []