Add Origin Trials Test interface, rather than attaching trials directly to internals.

third_party/WebKit/Source/core/core_idl_files.gni

Index: third_party/WebKit/Source/core/core_idl_files.gni
diff --git a/third_party/WebKit/Source/core/core_idl_files.gni b/third_party/WebKit/Source/core/core_idl_files.gni
index c53ac6a77fabdc4dc4e490fb535a31f733ebadb9..fec46121020e4097d33701e95873486d8f9f78cb 100644
--- a/third_party/WebKit/Source/core/core_idl_files.gni
+++ b/third_party/WebKit/Source/core/core_idl_files.gni
@@ -580,6 +580,7 @@ webcore_testing_idl_files =
                     "testing/InternalSettings.idl",
                     "testing/LayerRect.idl",
                     "testing/LayerRectList.idl",
+                    "testing/OriginTrialsTest.idl",
                     "testing/PrivateScriptTest.idl",
                     "testing/TypeConversions.idl",
                     "testing/UnionTypesTest.idl",
@@ -592,14 +593,11 @@ webcore_testing_idl_with_modules_dependency_files =
     get_path_info([ "testing/Internals.idl" ], "abspath")
 
 webcore_testing_dependency_idl_files =
-    get_path_info(
-        [
-          "origin_trials/testing/InternalsFrobulate.idl",
-          "origin_trials/testing/InternalsFrobulateInterfaceBindings.idl",
-          "origin_trials/testing/WorkerInternalsFrobulate.idl",
-          "testing/PartialPrivateScriptTest.idl",
-        ],
-        "abspath")
+    get_path_info([
+                    "testing/OriginTrialsTestPartial.idl",
+                    "testing/PartialPrivateScriptTest.idl",
+                  ],
+                  "abspath")
 
 generated_webcore_testing_idl_files =
     get_path_info(