Created AttestationPolicyObserver.

chrome/browser/chromeos/policy/proto/chrome_device_policy.proto

Index: chrome/browser/chromeos/policy/proto/chrome_device_policy.proto
diff --git a/chrome/browser/chromeos/policy/proto/chrome_device_policy.proto b/chrome/browser/chromeos/policy/proto/chrome_device_policy.proto
index fd303e03a8a427f5724e242586100bf818d2c5e6..c9601fefb834595a110bd491c839406b8983ee57 100644
--- a/chrome/browser/chromeos/policy/proto/chrome_device_policy.proto
+++ b/chrome/browser/chromeos/policy/proto/chrome_device_policy.proto
@@ -271,6 +271,11 @@ message UptimeLimitProto {
   optional int64 uptime_limit = 1;
 }
 
+message AttestationSettingsProto {
+  // Whether attestation features are enabled for the device.
+  optional bool attestation_enabled = 1;
+}
+
 message ChromeDeviceSettingsProto {
   optional DevicePolicyRefreshRateProto device_policy_refresh_rate = 1;
   optional UserWhitelistProto user_whitelist = 2;
@@ -296,4 +301,5 @@ message ChromeDeviceSettingsProto {
   optional AllowRedeemChromeOsRegistrationOffersProto allow_redeem_offers = 22;
   optional StartUpFlagsProto start_up_flags = 23;
   optional UptimeLimitProto uptime_limit = 24;
+  optional AttestationSettingsProto attestation_settings = 25;
 }