Initial implementation of GetStackSample sampling profiler API.

src/vm-state.h

Index: src/vm-state.h
diff --git a/src/vm-state.h b/src/vm-state.h
index a72180ca45f4dcee0485209cff3162e5d73a8cb5..1f08a21b72cdec1aaad90c13dc7e21ce335410a2 100644
--- a/src/vm-state.h
+++ b/src/vm-state.h
@@ -11,6 +11,12 @@
 namespace v8 {
 namespace internal {
 
+// Logging and profiling.  A StateTag represents a possible state of
+// the VM. The logger maintains a stack of these. Creating a VMState
+// object enters a state by pushing on the stack, and destroying a
+// VMState object leaves a state by popping the current state from the
+// stack.
+

[yurys, 2014/09/23 14:57:53]

style: remove empty line.

[alph, 2014/09/24 13:12:18]

Done.

 template <StateTag Tag>
 class VMState BASE_EMBEDDED {
  public: