Expose a lower bound of malloc'd memory via heap statistics

test/cctest/compiler/test-instruction.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/code-generator.h"
 #include "src/compiler/common-operator.h"
 #include "src/compiler/graph.h"
 #include "src/compiler/instruction.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/machine-operator.h"
@@ skipping 250 matching lines @@
     CHECK(move);
     CHECK_EQ(1u, move->size());
     MoveOperands* cur = move->at(0);
     CHECK(op1.Equals(cur->source()));
     CHECK(op2.Equals(cur->destination()));
   }
 }
 
 
 TEST(InstructionOperands) {
-  Zone zone;
+  ZoneForTesting zone;
 
   {
     TestInstr* i = TestInstr::New(&zone, 101);
     CHECK_EQ(0, static_cast<int>(i->OutputCount()));
     CHECK_EQ(0, static_cast<int>(i->InputCount()));
     CHECK_EQ(0, static_cast<int>(i->TempCount()));
   }
 
   int vreg = 15;
   InstructionOperand outputs[] = {
@@ skipping 35 matching lines @@
           CHECK(temps[z].Equals(*m->TempAt(z)));
         }
       }
     }
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8