GN: only write targets that should be generated.

tools/gn/command_gen.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 "base/atomicops.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "base/timer/elapsed_timer.h"
@@ skipping 49 matching lines @@
   {
     base::AutoLock lock(write_info->lock);
     write_info->rules[target->toolchain()].emplace_back(
         target, std::move(rule));
   }
 
   g_scheduler->DecrementWorkCount();
 }
 
 // Called on the main thread.
-void ItemResolvedCallback(TargetWriteInfo* write_info,
-                          const BuilderRecord* record) {
+void ItemResolvedAndGeneratedCallback(TargetWriteInfo* write_info,
+                                      const BuilderRecord* record) {
   const Item* item = record->item();
   const Target* target = item->AsTarget();
   if (target) {
     g_scheduler->IncrementWorkCount();
     g_scheduler->ScheduleWork(base::Bind(&BackgroundDoWrite,
                                          write_info, target));
   }
 }
 
 // Returns a pointer to the target with the given file as an output, or null
@@ skipping 298 matching lines @@
   if (!setup->DoSetup(args[0], true))
     return 1;
 
   const base::CommandLine* command_line =
       base::CommandLine::ForCurrentProcess();
   if (command_line->HasSwitch(kSwitchCheck))
     setup->set_check_public_headers(true);
 
   // Cause the load to also generate the ninja files for each target.
   TargetWriteInfo write_info;
-  setup->builder().set_resolved_callback(
-      base::Bind(&ItemResolvedCallback, &write_info));
+  setup->builder().set_resolved_and_generated_callback(
+      base::Bind(&ItemResolvedAndGeneratedCallback, &write_info));
 
   // Do the actual load. This will also write out the target ninja files.
   if (!setup->Run())
     return 1;
 
   // Sort the targets in each toolchain according to their label. This makes
   // the ninja files have deterministic content.
   for (auto& cur_toolchain : write_info.rules) {
     std::sort(cur_toolchain.second.begin(), cur_toolchain.second.end(),
               [](const NinjaWriter::TargetRulePair& a,
@@ skipping 42 matching lines @@
             setup->scheduler().input_file_manager()->GetInputFileCount()) +
         " files in " +
         base::Int64ToString(elapsed_time.InMilliseconds()) + "ms\n";
     OutputString(stats);
   }
 
   return 0;
 }
 
 }  // namespace commands