Fix the error message widget

lib/src/report.dart

Index: lib/src/report.dart
diff --git a/lib/src/report.dart b/lib/src/report.dart
index 6c74fe1ee2c435217d4c3273bac07f1a8ecb2238..7601570ea22fe231969134da328898881df9201a 100644
--- a/lib/src/report.dart
+++ b/lib/src/report.dart
@@ -137,7 +137,15 @@ class SummaryReporter implements AnalysisErrorListener {
     var span = _toSpan(_context, error);
     var summary = _getIndividualSummary(error.source.uri);
     if (summary is LibrarySummary) {
-      summary.countSourceLines(_context, error.source);
+      summary.recordSourceLines(error.source.uri, () {
+        // TODO(jmesserly): parsing is serious overkill for this.
+        // Should be cached, but still.
+        // On the other hand, if we are going to parse, we could get a much better
+        // source lines of code estimate by excluding things like comments,
+        // blank lines, and closing braces.
+        var unit = _context.parseCompilationUnit(error.source);
+        return unit.lineInfo.getLocation(unit.endToken.end).lineNumber;
+      });
     }
     summary.messages.add(new MessageSummary(errorCodeName(code),
         code.errorSeverity.displayName, span, error.message));