Move part of metrics from chrome/common to components

components/metrics.gypi

Index: components/metrics.gypi
diff --git a/components/metrics.gypi b/components/metrics.gypi
index 6036cae0cf91e3ef123fbdb65ffb35b7a63ebd35..e0fe84889fe14dcbc611a7e4d04047a580221611 100644
--- a/components/metrics.gypi
+++ b/components/metrics.gypi
@@ -12,11 +12,35 @@
       ],
       'dependencies': [
         '../base/base.gyp:base',
+        'component_metrics_proto',
       ],
       'sources': [
         'metrics/metrics_hashes.cc',
         'metrics/metrics_hashes.h',
+        'metrics/metrics_log_base.cc',
+        'metrics/metrics_log_base.h',
+        'metrics/metrics_log_manager.cc',
+        'metrics/metrics_log_manager.h',
       ],
     },
+    {
+      # Protobuf compiler / generator for UMA (User Metrics Analysis).
+      'target_name': 'component_metrics_proto',

[Alexei Svitkine (slow), 2014/04/22 15:28:10]

I think you will need to add an explicit dependency on this sub-library to
targets that include the proto headers. Transitivity doesn't work in this case.

This is confusing but basically, it's because the gyp dependency graph specifies
dependencies that are needed for linking, rather than compiling. So without the
explicit dependency, code that includes histogram_event.pb.h will start to be
compiled before histogram_event.pb.h is generated.

[bsimonnet, 2014/04/22 16:52:43]

I added a dependency on components.gyp:component_metrics_proto for
chrome_browser.
Do we need the same for chrome_tests_unit.gyp ?
(chrome/browser/metrics/extension_metrics_unittest.cc include a protobuf file)
It depends on chromium_browser_dependencies currently. Would it have the same
problem ?

On 2014/04/22 15:28:10, Alexei Svitkine wrote:

[Alexei Svitkine (slow), 2014/04/22 20:51:17]

It's probably needed. See some of the latter commits in http://crbug.com/266007
where I encountered this when making variations a component.

I think if you clean your output dir then build the specific target you're
wondering about, you can check whether it fails or not.

+      'type': 'static_library',
+      'sources': [
+        'metrics/proto/chrome_user_metrics_extension.proto',
+        'metrics/proto/histogram_event.proto',
+        'metrics/proto/omnibox_event.proto',
+        'metrics/proto/perf_data.proto',
+        'metrics/proto/profiler_event.proto',
+        'metrics/proto/system_profile.proto',
+        'metrics/proto/user_action_event.proto',
+      ],
+      'variables': {
+        'proto_in_dir': 'metrics/proto',
+        'proto_out_dir': 'components/metrics/proto',
+      },
+      'includes': [ '../build/protoc.gypi' ],
+    },
   ],
 }