VM: Clear all *_to_retain maps when resetting the precompiler state

runtime/vm/precompiler.cc

 // Copyright (c) 2015, 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/precompiler.h"
 
 #include "vm/aot_optimizer.h"
 #include "vm/assembler.h"
 #include "vm/ast_printer.h"
 #include "vm/branch_optimizer.h"
@@ skipping 2941 matching lines @@
 void Precompiler::ResetPrecompilerState() {
   changed_ = false;
   function_count_ = 0;
   class_count_ = 0;
   selector_count_ = 0;
   dropped_function_count_ = 0;
   dropped_field_count_ = 0;
   ASSERT(pending_functions_.Length() == 0);
   sent_selectors_.Clear();
   enqueued_functions_.Clear();
+
+  classes_to_retain_.Clear();
   consts_to_retain_.Clear();
+  fields_to_retain_.Clear();
+  functions_to_retain_.Clear();
+  typeargs_to_retain_.Clear();
+  types_to_retain_.Clear();
 
   Library& lib = Library::Handle(Z);
   Class& cls = Class::Handle(Z);
 
   for (intptr_t i = 0; i < libraries_.Length(); i++) {
     lib ^= libraries_.At(i);
     ClassDictionaryIterator it(lib, ClassDictionaryIterator::kIteratePrivate);
     while (it.HasNext()) {
       cls = it.GetNextClass();
       if (cls.IsDynamicClass()) {
@@ skipping 676 matching lines @@
 
   ASSERT(FLAG_precompiled_mode);
   const bool optimized = function.IsOptimizable();  // False for natives.
   DartPrecompilationPipeline pipeline(zone, field_type_map);
   return PrecompileFunctionHelper(precompiler, &pipeline, function, optimized);
 }
 
 #endif  // DART_PRECOMPILER
 
 }  // namespace dart