Sync metrics protos with google3

BUG=878604

Change-Id: I20d281d9b03fbb41c2cac72586a60949fc73a860
Reviewed-on: https://chromium-review.googlesource.com/1197269Reviewed-by: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Mike Wittman <wittman@chromium.org>
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#587785}

third_party/metrics_proto/README.chromium

 Name: Metrics Protos
 Short Name: metrics_proto
 URL: This is the canonical public repository
-Version: 210142511
-Date: 2018/08/24 UTC
+Version: 210962504
+Date: 2018/08/30 UTC
 License: BSD
 Security Critical: Yes
 

third_party/metrics_proto/cast_logs.proto

@@ -160,7 +160,7 @@ message CastLogsProto {
   repeated CastConnectionInfo cast_connection_info = 2;
 
   // Stores Cast-enabled device specific events with a various context data.
-  // Next tag: 18
+  // Next tag: 19
   message CastEventProto {
     // The name of the action, hashed by same logic used to hash user action
     // event and histogram.
@@ -203,6 +203,8 @@ message CastLogsProto {
 
     optional string aogh_request_id = 16;
 
+    optional int64 aogh_local_agent_id = 18;
+
     // Optional value associated with the event. For example, may be used for
     // error codes.
     message Metadata {

third_party/metrics_proto/sampled_profile.proto

@@ -46,6 +46,11 @@ message SampledProfile {
 
     // The profile was collected after a thread was determined to be hung.
     THREAD_HUNG = 6;
+
+    // The heap profile was triggered by periodic sampling. The time intervals
+    // between trigger events conform to the Poisson process with certain mean
+    // interval between collections.
+    PERIODIC_HEAP_COLLECTION = 7;
   }
   optional TriggerEvent trigger_event = 1;
 

third_party/metrics_proto/system_profile.proto

@@ -960,6 +960,7 @@ message SystemProfileProto {
     RTANALYTICS_LIGHT = 21;
     RTANALYTICS_FULL = 22;
     CELLULAR = 23;
+    DEMO_MODE_RESOURCES = 24;
   }
 
   // Information about what Chrome components are registered and at which