Add TranslateEventProto to UMA metrics

components/metrics/proto/chrome_user_metrics_extension.proto

Index: components/metrics/proto/chrome_user_metrics_extension.proto
diff --git a/components/metrics/proto/chrome_user_metrics_extension.proto b/components/metrics/proto/chrome_user_metrics_extension.proto
index 4b9bf68be16a5555d717aa625721f3991333158f..77950f975a7c28165e699ddfe88b5cc06afd2363 100644
--- a/components/metrics/proto/chrome_user_metrics_extension.proto
+++ b/components/metrics/proto/chrome_user_metrics_extension.proto
@@ -18,11 +18,12 @@ import "memory_leak_report.proto";
 import "omnibox_event.proto";
 import "profiler_event.proto";
 import "system_profile.proto";
+import "translate_event.proto";
 import "user_action_event.proto";
 import "perf_data.proto";
 import "sampled_profile.proto";
 
-// Next tag: 13
+// Next tag: 16
 message ChromeUserMetricsExtension {
   // The product (i.e. end user application) for a given UMA log.
   enum Product {
@@ -68,6 +69,7 @@ message ChromeUserMetricsExtension {
   repeated OmniboxEventProto omnibox_event = 5;
   repeated HistogramEventProto histogram_event = 6;
   repeated ProfilerEventProto profiler_event = 7;
+  repeated TranslateEventProto translate_event = 15;
 
   // This field is no longer used. Use |sampled_profile| instead.
   repeated PerfDataProto perf_data = 8 [deprecated=true];