Add pause_after_load to the config file.

lib/src/runner/configuration/load.dart

Index: lib/src/runner/configuration/load.dart
diff --git a/lib/src/runner/configuration/load.dart b/lib/src/runner/configuration/load.dart
index 6fcb15e30a67672bc0b9af5efa8506bb33365e00..4f1684b0a62691f0566765f99480766b70485af1 100644
--- a/lib/src/runner/configuration/load.dart
+++ b/lib/src/runner/configuration/load.dart
@@ -128,6 +128,7 @@ class _ConfigurationLoader {
   /// runner-level configuration fields.
   Configuration _loadRunnerConfig() {
     if (!_runnerConfig) {
+      _disallow("pause_after_load");
       _disallow("reporter");
       _disallow("pub_serve");
       _disallow("concurrency");
@@ -140,6 +141,8 @@ class _ConfigurationLoader {
       return Configuration.empty;
     }
 
+    var pauseAfterLoad = _getBool("pause_after_load");
+
     var reporter = _getString("reporter");
     if (reporter != null && !allReporters.contains(reporter)) {
       _error('Unknown reporter "$reporter".', "reporter");
@@ -183,6 +186,7 @@ class _ConfigurationLoader {
     var excludeTags = _parseBooleanSelector("exclude_tags");
 
     return new Configuration(
+        pauseAfterLoad: pauseAfterLoad,
         reporter: reporter,
         pubServePort: pubServePort,
         concurrency: concurrency,