Minor cleanups: use GrowableArray::is_empty instead of ::length() == 0

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 426 matching lines @@
     this->num_fixed_parameters++;
     ParamDesc param;
     param.name_pos = name_pos;
     param.name = &String::ZoneHandle(String::NewSymbol(name));
     param.is_final = true;
     param.type = type;
     this->parameters->Add(param);
   }
 
   void AddReceiver(intptr_t name_pos) {
-    ASSERT(this->parameters->length() == 0);
+    ASSERT(this->parameters->is_empty());
     // The receiver does not need to be type checked.
     AddFinalParameter(name_pos,
                       kThisName,
                       &Type::ZoneHandle(Type::DynamicType()));
   }
 
   void SetImplicitlyFinal() {
     implicitly_final = true;
   }
 
@@ skipping 8201 matching lines @@
 void Parser::SkipQualIdent() {
   ASSERT(IsIdentifier());
   ConsumeToken();
   if (CurrentToken() == Token::kPERIOD) {
     ConsumeToken();  // Consume the kPERIOD token.
     ExpectIdentifier("identifier expected after '.'");
   }
 }
 
 }  // namespace dart