Partially revert r26703 and omit regular code generation for implicit accessors.

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/code_patcher.h"
 #include "vm/compiler.h"
 #include "vm/isolate.h"
 #include "vm/log.h"
@@ skipping 730 matching lines @@
 
   for (intptr_t i = 0; i < table.Length(); i += Code::kSCallTableEntryLength) {
     pc_offset ^= table.At(i + Code::kSCallTableOffsetEntry);
     target ^= table.At(i + Code::kSCallTableFunctionEntry);
     if (target.IsNull()) {
       target_code ^= table.At(i + Code::kSCallTableCodeEntry);
       ASSERT(!target_code.IsNull());
       ASSERT(!target_code.IsFunctionCode());
       // Allocation stub or AllocateContext or AllocateArray or ...
     } else {
+      // Static calls initially call the CallStaticFunction stub because
+      // their target might not be compiled yet. After tree shaking, all
+      // static call targets are compiled.
       // Cf. runtime entry PatchStaticCall called from CallStaticFunction stub.
       ASSERT(target.HasCode());
       target_code ^= target.CurrentCode();
       CodePatcher::PatchStaticCallAt(pc_offset.Value() + code.EntryPoint(),
                                      code, target_code);
     }
   }
+
+  // We won't patch static calls anymore, so drop the static call table to save
+  // space.
   code.set_static_calls_target_table(Object::empty_array());
 }
 
 }  // namespace dart