Add optional public header checking to GN build

tools/gn/ninja_binary_target_writer.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "tools/gn/ninja_binary_target_writer.h"
 
 #include <set>
 
 #include "base/strings/string_util.h"
 #include "tools/gn/config_values_extractors.h"
@@ skipping 133 matching lines @@
 void NinjaBinaryTargetWriter::WriteSources(
     std::vector<OutputFile>* object_files) {
   const Target::FileList& sources = target_->sources();
   object_files->reserve(sources.size());
 
   std::string implicit_deps = GetSourcesImplicitDeps();
 
   for (size_t i = 0; i < sources.size(); i++) {
     const SourceFile& input_file = sources[i];
 
-    SourceFileType input_file_type = GetSourceFileType(input_file,
-                                                       settings_->target_os());
+    SourceFileType input_file_type = GetSourceFileType(input_file);
     if (input_file_type == SOURCE_UNKNOWN)
       continue;  // Skip unknown file types.
     std::string command =
         helper_.GetRuleForSourceType(settings_, input_file_type);
     if (command.empty())
       continue;  // Skip files not needing compilation.
 
     OutputFile output_file = helper_.GetOutputFileForSource(
         target_, input_file, input_file_type);
     object_files->push_back(output_file);
@@ skipping 256 matching lines @@
   if (dep->output_type() == Target::SOURCE_SET) {
     if (target_->output_type() == Target::SOURCE_SET) {
       // When a source set depends on another source set, add it as a data
       // dependency so if the user says "ninja second_source_set" it will
       // also compile the first (what you would expect) even though we'll
       // never do anything with the first one's files.
       non_linkable_deps->push_back(dep);
     } else {
       // Linking in a source set, copy its object files.
       for (size_t i = 0; i < dep->sources().size(); i++) {
-        SourceFileType input_file_type = GetSourceFileType(
-            dep->sources()[i], dep->settings()->target_os());
+        SourceFileType input_file_type = GetSourceFileType(dep->sources()[i]);
         if (input_file_type != SOURCE_UNKNOWN &&
             input_file_type != SOURCE_H) {
           // Note we need to specify the target as the source_set target
           // itself, since this is used to prefix the object file name.
           extra_object_files->insert(helper_.GetOutputFileForSource(
               dep, dep->sources()[i], input_file_type));
         }
       }
     }
   } else if (can_link_libs && dep->IsLinkable()) {
@@ skipping 17 matching lines @@
     }
 
     // Data files.
     const std::vector<SourceFile>& data = target_->data();
     for (size_t i = 0; i < data.size(); i++) {
       out_ << " ";
       path_output_.WriteFile(out_, data[i]);
     }
   }
 }