Support deps for actions in GN.

tools/gn/ninja_target_writer.cc

Index: tools/gn/ninja_target_writer.cc
diff --git a/tools/gn/ninja_target_writer.cc b/tools/gn/ninja_target_writer.cc
index 6be8c966fa5af7516b6e173fc50abd39a252cb2d..1b5a8deb602a3f2023d00e3ff7bcc9b525fafb01 100644
--- a/tools/gn/ninja_target_writer.cc
+++ b/tools/gn/ninja_target_writer.cc
@@ -84,12 +84,14 @@ void NinjaTargetWriter::RunAndWriteFile(const Target* target,
                   static_cast<int>(contents.size()));
 }
 
-std::string NinjaTargetWriter::WriteInputDepsStampAndGetDep() const {
+std::string NinjaTargetWriter::WriteInputDepsStampAndGetDep(
+    const std::vector<const Target*>& extra_hard_deps) const {
   // For an action (where we run a script only once) the sources are the same
   // as the source prereqs.
   bool list_sources_as_input_deps = target_->output_type() == Target::ACTION;
 
-  if (target_->source_prereqs().empty() &&
+  if (extra_hard_deps.empty() &&
+      target_->source_prereqs().empty() &&
       target_->recursive_hard_deps().empty() &&
       (!list_sources_as_input_deps || target_->sources().empty()))
     return std::string();  // No input/hard deps.
@@ -133,6 +135,13 @@ std::string NinjaTargetWriter::WriteInputDepsStampAndGetDep() const {
     path_output_.WriteFile(out_, helper_.GetTargetOutputFile(*i));
   }
 
+  // Extra hard deps passed in.
+  for (size_t i = 0; i < extra_hard_deps.size(); i++) {
+    out_ << " ";
+    path_output_.WriteFile(out_,
+        helper_.GetTargetOutputFile(extra_hard_deps[i]));
+  }
+
   out_ << "\n";
   return " | " + stamp_file_string;
 }