[PATCH] [lsan] Prettify LSan reports and add a summary

[Kostya Serebryany]

  LGTM


================
Comment at: lib/lsan/lsan_common.cc:417
@@ +416,3 @@
+  }
+  Printf("SUMMARY: LeakSanitizer: %llu bytes leaked.\n", bytes_leaked);
+}
----------------
I'd still print X bytes leaked from Y allocations


http://llvm-reviews.chandlerc.com/D859

BRANCH
  feat/lsan/reporting

ARCANIST PROJECT
  compiler-rt