Heap profiler: aggregate retainers count of equivalent clusters.

test/cctest/test-heap-profiler.cc

Index: test/cctest/test-heap-profiler.cc
diff --git a/test/cctest/test-heap-profiler.cc b/test/cctest/test-heap-profiler.cc
index f8e5a6b755ff423a9202e31b5673e8cba64db2dd..1e9cb7355773ff2d9e32054807cf64a3e10658f3 100644
--- a/test/cctest/test-heap-profiler.cc
+++ b/test/cctest/test-heap-profiler.cc
@@ -322,7 +322,14 @@ TEST(RetainerProfile) {
   }
   RetainerProfilePrinter printer;
   ret_profile.DebugPrintStats(&printer);
-  CHECK_EQ("(global property);1,B;2,C;2", printer.GetRetainers("A"));
+  const char* retainers_of_a = printer.GetRetainers("A");
+  // The order of retainers is unspecified, so we check string length, and
+  // verify each retainer separately.
+  CHECK_EQ(static_cast<int>(strlen("(global property);1,B;2,C;2")),
+           static_cast<int>(strlen(retainers_of_a)));
+  CHECK(strstr(retainers_of_a, "(global property);1") != NULL);
+  CHECK(strstr(retainers_of_a, "B;2") != NULL);
+  CHECK(strstr(retainers_of_a, "C;2") != NULL);
   CHECK_EQ("(global property);2", printer.GetRetainers("B"));
   CHECK_EQ("(global property);1", printer.GetRetainers("C"));
 }