Rename TrialsSeed proto to VariationsSeed.

This matches to how most of the code / documentation
was referring to it already and remains compatible
with the existing payload.

BUG=none
TEST=Existing unit tests. Also, verified manually that a seed received
from the server is still accepted and works correctly.

[email protected]

Review URL: https://codereview.chromium.org/23568004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@220943 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/components/variations/variations_seed_processor_unittest.cc b/components/variations/variations_seed_processor_unittest.cc
index 6a41ce21..85692f9 100644
--- a/components/variations/variations_seed_processor_unittest.cc
+++ b/components/variations/variations_seed_processor_unittest.cc
@@ -396,7 +396,7 @@
   const std::string kTrialName = "A";
   const std::string kGroup1Name = "Group1";
 
-  TrialsSeed seed;
+  VariationsSeed seed;
   Study* study1 = seed.add_study();
   study1->set_name(kTrialName);
   study1->set_default_experiment_name("Default");