Remove the outermost folded frame for terse stack traces.

lib/src/chain.dart

Index: lib/src/chain.dart
diff --git a/lib/src/chain.dart b/lib/src/chain.dart
index 99726f38916b49218d6f398262b435a7839676f5..9555e76fa0938202f53cb34300adef6cd395a88f 100644
--- a/lib/src/chain.dart
+++ b/lib/src/chain.dart
@@ -155,9 +155,14 @@ class Chain implements StackTrace {
     var foldedTraces = traces.map(
         (trace) => trace.foldFrames(predicate, terse: terse));
     var nonEmptyTraces = foldedTraces.where((trace) {
-      // Ignore traces that contain only folded frames. These traces will be
-      // folded into a single frame each.
-      return trace.frames.length > 1;
+      // Ignore traces that contain only folded frames.
+      if (trace.frames.length > 1) return true;
+
+      // In terse mode, the trace may have removed an outer folded frame,
+      // leaving a single non-folded frame. We can detect a folded frame because
+      // it has no line information.
+      if (!terse) return false;
+      return trace.frames.single.line != null;
     });
 
     // If all the traces contain only internal processing, preserve the last