predictors: Add a origin for prefetch requests, remove the URL/host settings.

chrome/browser/predictors/resource_prefetch_predictor_unittest.cc

Index: chrome/browser/predictors/resource_prefetch_predictor_unittest.cc
diff --git a/chrome/browser/predictors/resource_prefetch_predictor_unittest.cc b/chrome/browser/predictors/resource_prefetch_predictor_unittest.cc
index a99e0afd23777c3561f350d3aceb141b1c9b3664..4ad1343e9c1b0e528b3ef1cfe42825cff7333e48 100644
--- a/chrome/browser/predictors/resource_prefetch_predictor_unittest.cc
+++ b/chrome/browser/predictors/resource_prefetch_predictor_unittest.cc
@@ -243,8 +243,7 @@ class ResourcePrefetchPredictorTest : public testing::Test {
     config.min_resource_confidence_to_trigger_prefetch = 0.5;
 
     // TODO(shishir): Enable the prefetching mode in the tests.
-    config.mode |= ResourcePrefetchPredictorConfig::URL_LEARNING;
-    config.mode |= ResourcePrefetchPredictorConfig::HOST_LEARNING;
+    config.mode |= ResourcePrefetchPredictorConfig::LEARNING;
     predictor_.reset(new ResourcePrefetchPredictor(config, profile_.get()));
     predictor_->set_mock_tables(mock_tables_);
   }