Added support of the PlatformToolset property to Gyp (MSBuild only).

pylib/gyp/generator/msvs.py

Index: pylib/gyp/generator/msvs.py
diff --git a/pylib/gyp/generator/msvs.py b/pylib/gyp/generator/msvs.py
index a4c6efd1a466c97afbffd00938fb8e63a0727dfa..068bd191d6731f1807e8fa8634e00730c269f8ab 100644
--- a/pylib/gyp/generator/msvs.py
+++ b/pylib/gyp/generator/msvs.py
@@ -833,6 +833,20 @@ def _GetGuidOfProject(proj_path, spec):
   return guid
 
 
+def _GetMsbuildToolsetOfProject(proj_path, spec):
+  """Get the platform toolset for the project.
+
+  Arguments:
+    proj_path: Path of the vcproj or vcxproj file to generate.
+    spec: The target dictionary containing the properties of the target.
+  Returns:
+    the platform toolset string or None.
+  """
+  # Pluck out the default configuration.
+  default_config = _GetDefaultConfiguration(spec)
+  return default_config.get('msbuild_toolset')
+
+
 def _GenerateProject(project, options, version, generator_flags):
   """Generates a vcproj file.
 
@@ -1638,6 +1652,9 @@ def _CreateProjectObjects(target_list, target_dicts, options, msvs_version):
         build_file=build_file,
         config_platform_overrides=overrides,
         fixpath_prefix=fixpath_prefix)
+    # Set project toolset if any (MS build only)
+    if msvs_version.UsesVcxproj():
+      obj.set_msbuild_toolset(_GetMsbuildToolsetOfProject(proj_path, spec))
     projects[qualified_target] = obj
   # Set all the dependencies
   for project in projects.values():
@@ -2401,6 +2418,18 @@ def _GetMSBuildConfigurationDetails(spec, build_file):
   return _GetMSBuildPropertyGroup(spec, 'Configuration', properties)
 
 
+def _GetMSBuildLocalProperties(msbuild_toolset):
+  # Currently the only local property we support is PlatformToolset
+  properties = {}
+  if msbuild_toolset:
+    properties = [
+        ['PropertyGroup', {'Label': 'Locals'},
+          ['PlatformToolset', msbuild_toolset],
+        ]
+      ]
+  return properties
+
+
 def _GetMSBuildPropertySheets(configurations):
   user_props = r'$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props'
   return [
@@ -2834,6 +2863,7 @@ def _GenerateMSBuildProject(project, options, version, generator_flags):
   content += _GetMSBuildGlobalProperties(spec, project.guid, project_file_name)
   content += import_default_section
   content += _GetMSBuildConfigurationDetails(spec, project.build_file)
+  content += _GetMSBuildLocalProperties(project.msbuild_toolset)
   content += import_cpp_props_section
   content += _GetMSBuildExtensions(props_files_of_rules)
   content += _GetMSBuildPropertySheets(configurations)