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

test/cctest/test-liveedit.cc

Index: test/cctest/test-liveedit.cc
diff --git a/test/cctest/test-liveedit.cc b/test/cctest/test-liveedit.cc
index b8cf4061302ac98214b1f0eca317a932a63c6a0a..63063bd3f35be90d8e478562b7c855350f011537 100644
--- a/test/cctest/test-liveedit.cc
+++ b/test/cctest/test-liveedit.cc
@@ -95,7 +95,7 @@ void CompareStringsOneWay(const char* s1, const char* s2,
                           int expected_diff_parameter = -1) {
   StringCompareInput input(s1, s2);
 
-  Zone zone;
+  ZoneForTesting zone;
 
   DiffChunkStruct* first_chunk;
   ListDiffOutputWriter writer(&first_chunk, &zone);