Move time.ts to the base directory.

Change-Id: Iace52240b216cb51fd969e9ce90655c43a2642f9
diff --git a/ui/src/controller/aggregation/counter_aggregation_controller.ts b/ui/src/controller/aggregation/counter_aggregation_controller.ts
index 41a47fe..3c3cf15 100644
--- a/ui/src/controller/aggregation/counter_aggregation_controller.ts
+++ b/ui/src/controller/aggregation/counter_aggregation_controller.ts
@@ -12,10 +12,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+import {Duration} from '../../base/time';
 import {ColumnDef} from '../../common/aggregation_data';
 import {Engine} from '../../common/engine';
 import {Area, Sorting} from '../../common/state';
-import {Duration} from '../../common/time';
 import {globals} from '../../frontend/globals';
 import {Config, COUNTER_TRACK_KIND} from '../../tracks/counter';