Remove support for legacy abstract declarations

runtime/vm/parser.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/parser.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
 #include "vm/compiler_stats.h"
@@ skipping 13 matching lines @@
 
 DEFINE_FLAG(bool, enable_asserts, false, "Enable assert statements.");
 DEFINE_FLAG(bool, enable_type_checks, false, "Enable type checks.");
 DEFINE_FLAG(bool, trace_parser, false, "Trace parser operations.");
 DEFINE_FLAG(bool, warning_as_error, false, "Treat warnings as errors.");
 DEFINE_FLAG(bool, silent_warnings, false, "Silence warnings.");
 DEFINE_FLAG(bool, warn_legacy_map_literal, false,
             "Warning on legacy map literal syntax (single type argument)");
 DEFINE_FLAG(bool, strict_function_literals, false,
             "enforce new function literal rules");
-DEFINE_FLAG(bool, fail_legacy_abstract, false,
-            "error on explicit use of abstract on class members");
 
 static void CheckedModeHandler(bool value) {
   FLAG_enable_asserts = value;
   FLAG_enable_type_checks = value;
 }
 
 // --enable-checked-mode and --checked both enable checked mode which is
 // equivalent to setting --enable-asserts and --enable-type-checks.
 DEFINE_FLAG_HANDLER(CheckedModeHandler,
                     enable_checked_mode,
@@ skipping 2814 matching lines @@
     ErrorMsg(member.name_pos, "operator %s expects %"Pd" argument(s)",
         member.name->ToCString(), (expected_num_parameters - 1));
   }
 }
 
 
 void Parser::ParseClassMemberDefinition(ClassDesc* members) {
   TRACE_PARSER("ParseClassMemberDefinition");
   MemberDesc member;
   current_member_ = &member;
-  if ((CurrentToken() == Token::kABSTRACT) &&
-      (LookaheadToken(1) != Token::kLPAREN)) {
-    if (FLAG_fail_legacy_abstract) {
-      ErrorMsg("illegal use of abstract");
-    }
-    ConsumeToken();
-    member.has_abstract = true;
-  }
   if ((CurrentToken() == Token::kEXTERNAL) &&
       (LookaheadToken(1) != Token::kLPAREN)) {
     ConsumeToken();
     member.has_external = true;
   }
   if ((CurrentToken() == Token::kSTATIC) &&
       (LookaheadToken(1) != Token::kLPAREN)) {
     ConsumeToken();
     member.has_static = true;
   }
@@ skipping 6850 matching lines @@
 void Parser::SkipQualIdent() {
   ASSERT(IsIdentifier());
   ConsumeToken();
   if (CurrentToken() == Token::kPERIOD) {
     ConsumeToken();  // Consume the kPERIOD token.
     ExpectIdentifier("identifier expected after '.'");
   }
 }
 
 }  // namespace dart