Carry the client ID from the database all the way through upload

handler/mac/crash_report_exception_handler.cc

Index: handler/mac/crash_report_exception_handler.cc
diff --git a/handler/mac/crash_report_exception_handler.cc b/handler/mac/crash_report_exception_handler.cc
index 5fe76507750be58bd229d0609c1d410160360e82..e9d1115a82c828e7e889b6d7cff7040eab05c44e 100644
--- a/handler/mac/crash_report_exception_handler.cc
+++ b/handler/mac/crash_report_exception_handler.cc
@@ -21,6 +21,7 @@
 #include "base/logging.h"
 #include "base/mac/mach_logging.h"
 #include "base/strings/stringprintf.h"
+#include "client/settings.h"
 #include "minidump/minidump_file_writer.h"
 #include "snapshot/mac/process_snapshot_mac.h"
 #include "util/file/file_writer.h"
@@ -126,6 +127,16 @@ kern_return_t CrashReportExceptionHandler::CatchMachException(
     return KERN_FAILURE;
   }
 
+  UUID client_id;
+  Settings* const settings = database_->GetSettings();
+  if (settings) {
+    // If GetSettings() or GetClientID() fails, something else will log a
+    // message and client_id will be left at its default value, all zeroes,
+    // which is appropriate.
+    settings->GetClientID(&client_id);
+  }
+
+  process_snapshot.SetClientID(client_id);
   process_snapshot.SetAnnotationsSimpleMap(*process_annotations_);
 
   CrashReportDatabase::NewReport* new_report;