Fix protoc_java.gypi action dependency.

build/protoc_java.gypi

 # Copyright (c) 2012 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.
 
 # This file is meant to be included into a target to provide a rule
 # to invoke protoc in a consistent manner. This is only to be included
 # for Java targets. When including this file, a .jar-file will be generated.
 # For other targets, see protoc.gypi.
 #
 # To use this, create a gyp target with the following form:
@@ skipping 24 matching lines @@
 #
 # How the .jar-file is created is different than how protoc is used for other
 # targets, and as such, this lives in its own file.
 
 {
   'variables': {
     'protoc': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)protoc<(EXECUTABLE_SUFFIX)',
     'java_out_dir': '<(PRODUCT_DIR)/java_proto/<(_target_name)/src',
     'proto_in_dir%': '.',
     'stamp_file': '<(java_out_dir).stamp',
-    # Variables needed by java.gypi below.
+    'script': '<(DEPTH)/build/protoc_java.py',
+
+    # The rest of the variables here are for the java.gypi include.
     'package_name': '<(_target_name)',
     'java_in_dir': '<(DEPTH)/build/android/empty',
-    'script': '<(DEPTH)/build/protoc_java.py',
     'generated_src_dirs': ['<(java_out_dir)'],
+    # Adding the |stamp_file| to |additional_input_paths| makes the actions in
+    # the include of java.gypi depend on the genproto_java action.
+    'additional_input_paths': ['<(stamp_file)'],
   },
   'actions': [
     {
       'action_name': 'genproto_java',
       'inputs': [
         '<(script)',
         '<(protoc)',
         '<@(_sources)',
       ],
       # We do not know the names of the generated files, so we use a stamp.
@@ skipping 10 matching lines @@
       ],
       'message': 'Generating Java code from <(proto_in_dir)',
     },
   ],
   'dependencies': [
     '<(DEPTH)/third_party/protobuf/protobuf.gyp:protoc#host',
     '<(DEPTH)/third_party/protobuf/protobuf.gyp:protobuf_lite_javalib',
   ],
   'includes': [ 'java.gypi' ],
 }