Moving cpu profiling into its own thread.

src/platform-macos.cc

Index: src/platform-macos.cc
diff --git a/src/platform-macos.cc b/src/platform-macos.cc
index a216f6e4cacd2561cb983550ed64d6974dbd095f..af33346e983aca332dd2163131fd363130d989b3 100644
--- a/src/platform-macos.cc
+++ b/src/platform-macos.cc
@@ -910,6 +910,11 @@ Sampler::~Sampler() {
 }
 
 
+void Sampler::DoSample() {
+  // TODO: implement

[Jakob Kummerow, 2012/09/04 11:10:51]

If you want to commit this before implementing it for all platforms (the old
code would still work on those, right?), please add either your username to the
TODO ("TODO(rogulenko): implement"), or file a bug
(code.google.com/p/v8/issues/list) and put the bug number here ("TODO(12345):
implement").

Same comment for the other platforms.

+}
+
+
 void Sampler::Start() {
   ASSERT(!IsActive());
   SetActive(true);