Reduce copying in sending service responses.

runtime/vm/dart_api_impl.cc

 // Copyright (c) 2013, 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 "include/dart_api.h"
 #include "include/dart_mirrors_api.h"
 #include "include/dart_native_api.h"
 
 #include "platform/assert.h"
 #include "lib/stacktrace.h"
@@ skipping 6109 matching lines @@
 }
 
 
 static bool StreamTraceEvents(Dart_StreamConsumer consumer,
                               void* user_data,
                               JSONStream* js) {
   ASSERT(js != NULL);
   // Steal output from JSONStream.
   char* output = NULL;
   intptr_t output_length = 0;
-  js->Steal(const_cast<const char**>(&output), &output_length);
+  js->Steal(&output, &output_length);
   if (output_length < 3) {
     // Empty JSON array.
     free(output);
     return false;
   }
   // We want to send the JSON array without the leading '[' or trailing ']'
   // characters.
   ASSERT(output[0] == '[');
   ASSERT(output[output_length - 1] == ']');
   // Replace the ']' with the null character.
@@ skipping 439 matching lines @@
 
 DART_EXPORT bool Dart_IsPrecompiledRuntime() {
 #if defined(DART_PRECOMPILED_RUNTIME)
   return true;
 #else
   return false;
 #endif
 }
 
 }  // namespace dart