Fix dependencies on policy_component_test_support

components/policy/core/browser/BUILD.gn

Index: components/policy/core/browser/BUILD.gn
diff --git a/components/policy/core/browser/BUILD.gn b/components/policy/core/browser/BUILD.gn
index d6441ad1cbb8dc52f20a21ddf02d89532d0062af..ecee8e3aed6450c4f9226d70296de29a54de8a18 100644
--- a/components/policy/core/browser/BUILD.gn
+++ b/components/policy/core/browser/BUILD.gn
@@ -88,9 +88,12 @@ source_set("unit_tests") {
     "url_blacklist_policy_handler_unittest.cc",
   ]
   deps = [
-    "//components/policy:policy_component_test_support",
     "//components/url_formatter",
     "//testing/gmock",
     "//testing/gtest",
   ]
+
+  if (enable_configuration_policy) {

[bartfab (slow), 2015/09/08 15:01:03]

I cannot see the purpose of trying to build policy unit tests with policy
disabled at build-time?

[Tomasz Moniuszko, 2015/09/09 07:54:51]

//components/policy:policy_component_test_support is defined only if
enable_configuration_policy==true.

Do you think whole //components/policy/core/browser:unit_tests and
//components/policy/core/common:unit_tests (or even all targets in
//components/policy) should be conditionally defined?

On the other hand enable_configuration_policy causes some issues occasionally.
See https://codereview.chromium.org/952163002/,
https://codereview.chromium.org/1009883002,
https://codereview.chromium.org/1079083003 and
https://codereview.chromium.org/1133853005 (which is still hanging). It seems
enable_configuration_policy is now true for all Chromium configurations so maybe
it would be a better idea to remove it completely?

[bartfab (slow), 2015/09/14 17:38:56]

We do like the idea of a lighter-weight option for those who do not need policy.
But as you noted yourself, enable_configuration_policy=true for Chrome on all
platforms, which means that enable_configuration_policy=false gets no bot
coverage and slowly rots away. Fixes are welcome but we are not officially
maintaining this configuration in any way.

Regarding your specific CL: With your fix applied, does a
enable_configuration_policy=false build still build the unit_test target in this
file (I presume yes)? What happens if you run the tests (I presume they all
fail)? To me, the entire unit_tests target makes no sense if
enable_configuration_policy=false. The whole thing should be disabled.

componets/policy cannot be completely yanked when
enable_configuration_policy=false because there is a tiny bit of glue code that
is used unconditionally. But all the real functionality and tests should be
disabled.

[Tomasz Moniuszko, 2015/09/15 12:05:12]

Thank you for your reply. In Patch Set 2 I disabled unit_tests targets in
//components/policy/core/browser and //components/policy/core/common if
enable_configuration_policy=false as you suggested. Also two tests in
//components/search_engines:unit_tests and //components/sync_driver:unit_tests
are now included conditionally as they fail to link if
enable_configuration_policy=false.

+    deps += [ "//components/policy:policy_component_test_support" ]
+  }
 }