Use tcmalloc on Linux

DEPS

Index: DEPS
diff --git a/DEPS b/DEPS
index 20103b75e394c64cb94e4749f880b7a286f5f831..24b420e1cf25bf1ee3345389576b22b16e1e755f 100644
--- a/DEPS
+++ b/DEPS
@@ -34,6 +34,8 @@ vars = {
   "base_revision": "@672b04e54b937ec899429a6bd5409c5a6300d151",
   "buildtools_revision": "@565d04e8741429fb1b4f26d102f2c6c3b849edeb",
 
+  "gperftools_revision": "@7822b5b0b9fa7e016e1f6b46ea86f26f4691a457",
+
   # Revisions of /third_party/* dependencies.
   "args_tag": "@0.13.5",
   "async_tag": "@1.11.1",
@@ -167,6 +169,10 @@ deps = {
   Var("dart_root") + "/third_party/WebCore":
       "https://github.com/dart-lang/webcore.git" + Var("WebCore_rev"),
 
+  Var("dart_root") + "/third_party/tcmalloc/gperftools":
+      "https://github.com/gperftools/gperftools.git" +

[zra, 2016/09/13 15:59:00]

Bill, could we put this in the github mirror? Or is this okay to pull from
github?

+      Var("gperftools_revision"),
+
   Var("dart_root") + "/third_party/pkg/args":
       (Var("github_mirror") % "args") + Var("args_tag"),
   Var("dart_root") + "/third_party/pkg/async":