Rework definitions of 'gn_all' and related targets.

build/gn_migration.gypi

Index: build/gn_migration.gypi
diff --git a/build/gn_migration.gypi b/build/gn_migration.gypi
index 58e7ff5a91bb45054cb37a8ce3aedc9275bcfc97..73822fee5fed835b013752faae5b5e9c07f2c977 100644
--- a/build/gn_migration.gypi
+++ b/build/gn_migration.gypi
@@ -2,36 +2,46 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-# This file defines three targets that we are using to
-# track the progress of the GYP->GN migration:
+# This file defines five targets that we are using to track the progress of the
+# GYP->GN migration:
 #
-# If you run 'ninja gn_build gyp_remaining gyp_groups', and then
-# run 'ninja', the second ninja invocation should do nothing. This
-# indicates that everything built by a ninja build is in fact
-# listed in one of these targets.
+# 'both_gn_and_gyp' lists what GN is currently capable of building and should
+# match the 'both_gn_and_gyp' target in //BUILD.gn.
 #
-# 'gn_all' lists what GN is currently capable of building and should
-#          match the 'gn_all' target in //BUILD.gn.
+# 'gyp_all' Should include everything built when building "all"; i.e., if you
+# type 'ninja gyp_all' and then 'ninja all', the second build should do
+# nothing. 'gyp_all' should just depend on the other four targets.
 #
-# 'gyp_remaining' lists all of the targets that still need to be converted,
-#          i.e., all of the other (non-empty) targets that a GYP build
-#          will build.
+# 'gyp_groups' lists any empty (group) targets in the GYP build that are not
+# picked up by both_gn_and_gyp, gyp_only, or gyp_remaining; this is a separate
+# target to ensure that when we build it, only stamp targets file are we don't
+# accidentally pick up something not listed in one of the other two targets.
+#
+# 'gyp_only' lists any targets that are not meant to be ported over to the GN
+# build.
 #
-# 'gyp_groups' lists any empty (group) targets in the GYP build that
-#          are not picked up by gn_all or gyp_remaining; this is a
-#          separate target to ensure that when we build it, only
-#          stamp targets file are we don't accidentally pick up something
-#          not listed in one of the other two targets.
+# 'gyp_remaining' lists all of the targets that still need to be converted,
+# i.e., all of the other (non-empty) targets that a GYP build will build.
 #
-# TODO(GYP), TODO(dpranke) Add a build step to the bot that enforces the
-#          above contracts.
+# TODO(GYP): crbug.com/481694. Add a build step to the bot that enforces the
+# above contracts.
 
 {
   'targets': [
     {
-      # This target should mirror the structure of //:gn_all
-      # as closely as possible, for ease of comparison.
-      'target_name': 'gn_all',
+      'target_name': 'gyp_all',
+      'type': 'none',
+      'dependencies': [
+        'both_gn_and_gyp',
+        'gyp_groups',
+        'gyp_only',
+        'gyp_remaining',
+      ]
+    },
+    {
+      # This target should mirror the structure of //:both_gn_and_gyp
+      # in src/BUILD.gn as closely as possible, for ease of comparison.
+      'target_name': 'both_gn_and_gyp',
       'type': 'none',
       'dependencies': [
         '../base/base.gyp:base_i18n_perftests',