[TTS] Update fieldtrial names for CS IPH.

Updates some experiment names for the field trial testing config
to match what we want to use on the server.

BUG=822087

Change-Id: Ieb710725624a7e8a1134d195fc8208b33d864336
Reviewed-on: https://chromium-review.googlesource.com/967347Reviewed-by: Steven Holte <holte@chromium.org>
Commit-Queue: Donn Denman <donnd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543912}

testing/variations/fieldtrial_testing_config.json

@@ -149,7 +149,7 @@
             ],
             "experiments": [
                 {
-                    "name": "PromotePanelOpeningExperiment2",
+                    "name": "PromotePanelOpeningExperiment",
                     "params": {
                         "availability": ">=30",
                         "event_1": "name:contextual_search_promote_panel_open_iph_trigger;comparator:<2;window:680;storage:680",
@@ -172,7 +172,7 @@
             ],
             "experiments": [
                 {
-                    "name": "PromoteTapExperiment2",
+                    "name": "PromoteTapExperiment",
                     "params": {
                         "availability": ">=30",
                         "event_1": "name:contextual_search_panel_opened;comparator:>=2;window:90;storage:90",
@@ -195,7 +195,7 @@
             ],
             "experiments": [
                 {
-                    "name": "WebSearchExperiment2",
+                    "name": "WebSearchExperiment",
                     "params": {
                         "availability": ">=30",
                         "event_1": "name:web_search_performed;comparator:>=1;window:90;storage:90",