Updated enable-malloc-hooks flag to be disabled by default in debug mode.

runtime/vm/flag_list.h

 // 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.
 
 #ifndef RUNTIME_VM_FLAG_LIST_H_
 #define RUNTIME_VM_FLAG_LIST_H_
 
 // Don't use USING_DBC outside of this file.
 #if defined(TARGET_ARCH_DBC)
 #define USING_DBC true
 #else
 #define USING_DBC false
 #endif
 
 #if defined(TARGET_OS_FUCHSIA)
 #define USING_FUCHSIA true
 #else
 #define USING_FUCHSIA false
 #endif
 
 // Don't use USING_MULTICORE outside of this file.
 #if defined(ARCH_IS_MULTI_CORE)
 #define USING_MULTICORE true
 #else
 #define USING_MULTICORE false
 #endif
 
-#if defined(DEBUG)
-#define USING_DEBUG true
-#else
-#define USING_DEBUG false
-#endif
-
 // List of all flags in the VM.
 // Flags can be one of three categories:
 // * P roduct flags: Can be set in any of the deployment modes, including in
 //   production.
 // * R elease flags: Generally available flags except when building product.
 // * D ebug flags: Can only be set in debug VMs, which also have C++ assertions
 //   enabled.
 // * pre C ompile flags: Generally available flags except when building product
 //   or precompiled runtime.
 //
@@ skipping 23 matching lines @@
     "Deoptimizes we are about to return to Dart code from native entries.")    \
   C(deoptimize_every, 0, 0, int, 0,                                            \
     "Deoptimize on every N stack overflow checks")                             \
   R(disable_alloc_stubs_after_gc, false, bool, false, "Stress testing flag.")  \
   R(disassemble, false, bool, false, "Disassemble dart code.")                 \
   R(disassemble_optimized, false, bool, false, "Disassemble optimized code.")  \
   R(dump_megamorphic_stats, false, bool, false,                                \
     "Dump megamorphic cache statistics")                                       \
   R(dump_symbol_stats, false, bool, false, "Dump symbol table statistics")     \
   R(enable_asserts, false, bool, false, "Enable assert statements.")           \
-  R(enable_malloc_hooks, false, bool, USING_DEBUG,                             \
+  R(enable_malloc_hooks, false, bool, false,                                   \
     "Enable native memory statistic collection. Enabled by default in Debug "  \
     "mode")                                                                    \
   C(enable_mirrors, false, false, bool, true,                                  \
     "Disable to make importing dart:mirrors an error.")                        \
   R(enable_type_checks, false, bool, false, "Enable type checks.")             \
   R(error_on_bad_override, false, bool, false,                                 \
     "Report error for bad overrides.")                                         \
   R(error_on_bad_type, false, bool, false,                                     \
     "Report error for malformed types.")                                       \
   P(external_max_size, int, (kWordSize <= 4) ? 512 : 1024,                     \
@@ skipping 85 matching lines @@
   P(verbose_gc_hdr, int, 40, "Print verbose GC header interval.")              \
   R(verify_after_gc, false, bool, false,                                       \
     "Enables heap verification after GC.")                                     \
   R(verify_before_gc, false, bool, false,                                      \
     "Enables heap verification before GC.")                                    \
   D(verify_gc_contains, bool, false,                                           \
     "Enables verification of address contains during GC.")                     \
   D(verify_on_transition, bool, false, "Verify on dart <==> VM.")
 
 #endif  // RUNTIME_VM_FLAG_LIST_H_