Enable conditional directives by default.

pkg/analyzer/lib/src/generated/parser.dart

Index: pkg/analyzer/lib/src/generated/parser.dart
diff --git a/pkg/analyzer/lib/src/generated/parser.dart b/pkg/analyzer/lib/src/generated/parser.dart
index 7e5bee84bb505d0e294a11f32fa90248f44fe613..6eb4284db7ceec1413995d2571aaa0623e2f3005 100644
--- a/pkg/analyzer/lib/src/generated/parser.dart
+++ b/pkg/analyzer/lib/src/generated/parser.dart
@@ -2169,12 +2169,6 @@ class Parser {
   bool _inInitializer = false;
 
   /**
-   * A flag indicating whether the parser is to parse conditional directives
-   * syntax.
-   */
-  bool parseConditionalDirectives = false;
-
-  /**
    * A flag indicating whether the parser is to parse generic method syntax.
    */
   bool parseGenericMethods = false;
@@ -5360,10 +5354,8 @@ class Parser {
    */
   List<Configuration> _parseConfigurations() {
     List<Configuration> configurations = <Configuration>[];
-    if (parseConditionalDirectives) {
-      while (_matchesKeyword(Keyword.IF)) {
-        configurations.add(_parseConfiguration());
-      }
+    while (_matchesKeyword(Keyword.IF)) {
+      configurations.add(_parseConfiguration());
     }
     return configurations;
   }