fix cpp11 compile errors

runtime/vm/heap_histogram.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 "vm/heap_histogram.h"
 
 #include "platform/assert.h"
 #include "vm/flags.h"
 #include "vm/object.h"
 #include "vm/json_stream.h"
@@ skipping 106 matching lines @@
   // Finally print the sorted array.
   Class& cls = Class::Handle();
   String& str = String::Handle();
   Library& lib = Library::Handle();
   for (intptr_t pos = 0; pos < length; pos++) {
     Element* e = array[pos];
     if (e->count_ > 0) {
       cls = isolate_->class_table()->At(e->class_id_);
       str = cls.Name();
       lib = cls.library();
-      OS::Print("%9"Pd" %7"Pd" ",
+      OS::Print("%9" Pd " %7" Pd " ",
                 e->size_ / major_gc_count_,
                 e->count_ / major_gc_count_);
       if (e->class_id_ < kInstanceCid) {
         OS::Print("`%s`", str.ToCString());  // VM names.
       } else {
         OS::Print("%s", str.ToCString());
       }
       if (lib.IsNull()) {
         OS::Print("\n");
       } else {
@@ skipping 58 matching lines @@
   stream->PrintProperty("count", count_sum);
   stream->CloseObject();
   stream->CloseObject();
 
   // Deallocate the array for sorting.
   free(array);
 }
 
 
 }  // namespace dart