Handle invalid URIs in summaries.

pkg/analyzer/lib/src/task/dart.dart

Index: pkg/analyzer/lib/src/task/dart.dart
diff --git a/pkg/analyzer/lib/src/task/dart.dart b/pkg/analyzer/lib/src/task/dart.dart
index 05528d7f03960538894c15a1bc7dd2c17eab31bf..32a8bf44c9c03941fb9ad3b50c48e055fe3d0192 100644
--- a/pkg/analyzer/lib/src/task/dart.dart
+++ b/pkg/analyzer/lib/src/task/dart.dart
@@ -4258,8 +4258,12 @@ class ParseDartTask extends SourceBasedAnalysisTask {
     UriValidationCode code =
         UriBasedDirectiveImpl.validateUri(isImport, uriLiteral, uriContent);
     if (code == null) {
-      String encodedUriContent = Uri.encodeFull(uriContent);
-      return context.sourceFactory.resolveUri(_source, encodedUriContent);
+      try {
+        Uri.parse(uriContent);
+      } on FormatException {
+        return null;
+      }
+      return context.sourceFactory.resolveUri(_source, uriContent);
     } else if (code == UriValidationCode.URI_WITH_DART_EXT_SCHEME) {
       return null;
     } else if (code == UriValidationCode.URI_WITH_INTERPOLATION) {