Add build ID field to MemoryLeakReportProto

components/metrics/proto/memory_leak_report.proto

Index: components/metrics/proto/memory_leak_report.proto
diff --git a/components/metrics/proto/memory_leak_report.proto b/components/metrics/proto/memory_leak_report.proto
index bbd2dbc7a6615b1e56585d67f08cb3cd8e1b2f19..2a25f3857a1e31cd7e91df6de9ef8da31092821b 100644
--- a/components/metrics/proto/memory_leak_report.proto
+++ b/components/metrics/proto/memory_leak_report.proto
@@ -8,7 +8,7 @@ option optimize_for = LITE_RUNTIME;
 
 package metrics;
 
-// Next tag: 6
+// Next tag: 7
 message MemoryLeakReportProto {
   // The call stack at which the leak was found. This is a list of offsets
   // within the program binary. The first entry is the deepest level of the call
@@ -69,6 +69,12 @@ message MemoryLeakReportProto {
   }
   optional ProcessType source_process = 5;
 
+  // The build ID of the Chrome binary from which this leak report was obtained.
+  // The build ID is typically a 16- or 20-byte hash that is generated by the
+  // compiler that built the binary. This value will be read directly from the
+  // GNU build notes section of the Chrome binary.
+  optional bytes build_id = 6;
+
   //////////////////////////////////////////////////////////////////////////////
 
   // Represents a single snapshot of the internal bookkeeping of the Runtime