Added experiment IDs to API.

Bug: 951635
Change-Id: Ia4edd29e3ec2397d5e7f6be58d25982414ca2b30
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1564790
Commit-Queue: Vincent Boisselle <vincb@chromium.org>
Reviewed-by: Roger McFarlane <rogerm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#652333}

components/autofill/core/browser/proto/api_v1.proto

@@ -24,7 +24,7 @@ message AutofillPageResourceQueryRequest {
 
 // Request to retrieve field suggestions for multiple forms in a page. You can
 // see this as batched form requests.
-// Next ID: 3
+// Next ID: 4
 message AutofillPageQueryRequest {
   // Next ID: 3
   message Form {
@@ -54,6 +54,8 @@ message AutofillPageQueryRequest {
   optional string client_version = 1 [deprecated = true];
   // Forms in the same page for which we want fields suggestions.
   repeated Form forms = 2;
+  // The collection of server-side experiments to use.
+  repeated int64 experiments = 3;
 };
 
 // Response containing field suggestions from Autofill API for

components/autofill/core/browser/proto/legacy_proto_bridge.cc

@@ -56,6 +56,7 @@ AutofillQueryResponseContents::Field CreateLegacyFieldFromApiField(
 AutofillPageQueryRequest CreateApiRequestFromLegacyRequest(
     const AutofillQueryContents& legacy_request) {
   AutofillPageQueryRequest api_request;
+  *api_request.mutable_experiments() = legacy_request.experiments();
   api_request.set_client_version(legacy_request.client_version());
   for (const auto& legacy_form : legacy_request.form()) {
     *api_request.add_forms() = CreateApiFormFromLegacyForm(legacy_form);

components/autofill/core/browser/proto/legacy_proto_bridge_unittest.cc

@@ -70,6 +70,8 @@ AutofillQueryResponse::FormSuggestion::FieldSuggestion MakeFieldSuggestion(
 TEST(ProtoBridgeTest, TestCreateApiRequestFromLegacyRequest) {
   AutofillQueryContents legacy_request;
   legacy_request.set_client_version("dummy client v1");
+  legacy_request.add_experiments(1234);
+  legacy_request.add_experiments(5678);
   AutofillQueryContents::Form* new_form = legacy_request.add_form();
   new_form->set_signature(1234U);
   *new_form->mutable_form_metadata() = GetformMetadata();
@@ -86,6 +88,8 @@ TEST(ProtoBridgeTest, TestCreateApiRequestFromLegacyRequest) {
       CreateApiRequestFromLegacyRequest(legacy_request);
 
   EXPECT_EQ(api_request.client_version(), "dummy client v1");
+  EXPECT_EQ(api_request.experiments(0), 1234);
+  EXPECT_EQ(api_request.experiments(1), 5678);
   EXPECT_EQ(api_request.forms(0).signature(), 1234U);
   EXPECT_EQ(api_request.forms(0).metadata().id().encoding_type(),
             AutofillRandomizedValue::BIT_1);