Parse 'x.y' as PrefixedIdentifier, not PropertyAccess with Fasta.

pkg/analyzer/test/generated/parser_fasta_test.dart

Index: pkg/analyzer/test/generated/parser_fasta_test.dart
diff --git a/pkg/analyzer/test/generated/parser_fasta_test.dart b/pkg/analyzer/test/generated/parser_fasta_test.dart
index d7f17c7dec9f0ca63f6b8898d438d23f01c656a7..a5b10462a3f13843cff803d4e80c477e63d23423 100644
--- a/pkg/analyzer/test/generated/parser_fasta_test.dart
+++ b/pkg/analyzer/test/generated/parser_fasta_test.dart
@@ -285,14 +285,6 @@ class ComplexParserTest_Fasta extends FastaParserTestCase
 
   @override
   @failingTest
-  void test_assignmentExpression_prefixedIdentifier() {
-    // TODO(paulberry,ahe): Analyzer expects "x.y" to be parsed as a
-    // PrefixedIdentifier, even if x is not a prefix.
-    super.test_assignmentExpression_prefixedIdentifier();
-  }
-
-  @override
-  @failingTest
   void test_cascade_withAssignment() {
     // TODO(paulberry,ahe): AstBuilder doesn't implement
     // endConstructorReference().
@@ -416,12 +408,6 @@ class ExpressionParserTest_Fasta extends FastaParserTestCase
 
   @override
   @failingTest
-  void test_parseAssignableExpression_identifier_dot() {
-    super.test_parseAssignableExpression_identifier_dot();
-  }
-
-  @override
-  @failingTest
   void test_parseAwaitExpression() {
     super.test_parseAwaitExpression();
   }
@@ -747,18 +733,6 @@ class ExpressionParserTest_Fasta extends FastaParserTestCase
 
   @override
   @failingTest
-  void test_parsePostfixExpression_none_propertyAccess() {
-    super.test_parsePostfixExpression_none_propertyAccess();
-  }
-
-  @override
-  @failingTest
-  void test_parsePrefixedIdentifier_prefix() {
-    super.test_parsePrefixedIdentifier_prefix();
-  }
-
-  @override
-  @failingTest
   void test_parsePrimaryExpression_const() {
     super.test_parsePrimaryExpression_const();
   }
@@ -940,6 +914,12 @@ class FastaParserTestCase extends Object
   @override
   Expression parseAssignableSelector(String code, bool optional,
       {bool allowConditional: true}) {
+    if (optional) {
+      if (code.isEmpty) {
+        return _parseExpression('foo');
+      }
+      return _parseExpression('(foo)$code');
+    }
     return _parseExpression('foo$code');
   }