[Metrics] Move CachingPermutedEntropyProvider into the variations component.

components/variations.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.
 
 {
   'targets': [
     {
       'target_name': 'variations',
       'type': 'static_library',
       'include_dirs': [
         '..',
       ],
       'dependencies': [
         '../base/base.gyp:base',
         '../third_party/mt19937ar/mt19937ar.gyp:mt19937ar',
+        'variations_proto',
       ],
       'sources': [
+        'variations/caching_permuted_entropy_provider.cc',
+        'variations/caching_permuted_entropy_provider.h',
         'variations/entropy_provider.cc',
         'variations/entropy_provider.h',
         'variations/metrics_util.cc',
         'variations/metrics_util.h',
+        'variations/pref_names.cc',
+        'variations/pref_names.h',
         'variations/processed_study.cc',
         'variations/processed_study.h',
-        'variations/proto/variations_seed.proto',
-        'variations/proto/study.proto',
         'variations/study_filtering.cc',
         'variations/study_filtering.h',
         'variations/variations_associated_data.cc',
         'variations/variations_associated_data.h',
         'variations/variations_seed_processor.cc',
         'variations/variations_seed_processor.h',
         'variations/variations_seed_simulator.cc',
         'variations/variations_seed_simulator.h',
       ],
+    },
+    {
+      'target_name': 'variations_proto',

[Alexei Svitkine (slow), 2014/05/19 11:23:03]

I think it's OK to keep them in the same target (makes the build graph smaller).

But if you really insist of having a separate target, we need to update the
targets that depend on this (I think chrome_browser.gypi and maybe also
chrome_common.gypi) to explicitly depend on this target, since dependencies are
only transitive for linking, not for including generated proto headers.

[blundell, 2014/05/19 11:25:25]

I don't think they can be in the same target, as the order between the action
that generates the pb.h header and the compilation of the files including that
header wouldn't be defined AFAIK.

On 2014/05/19 11:23:03, Alexei Svitkine wrote:

[blundell, 2014/05/19 11:26:56]

Good point. We can do an export_dependent_settings in the variations target
instead, as that will export the hard_dependency to targets depending on
variations.

[Ilya Sherman, 2014/05/19 11:41:22]

Restored the original .gyp structure.

+      'type': 'static_library',
+      'sources': [
+        'variations/proto/permuted_entropy_cache.proto',
+        'variations/proto/study.proto',
+        'variations/proto/variations_seed.proto',
+      ],
       'variables': {
         'proto_in_dir': 'variations/proto',
         'proto_out_dir': 'components/variations/proto',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ],
 }