[turbofan] basic block profiler

src/compiler/schedule.h

Index: src/compiler/schedule.h
diff --git a/src/compiler/schedule.h b/src/compiler/schedule.h
index 070691e4c6e8af7d6293875bae714abfeead9cb9..2b15b664cc8fe6b2dd27c903317ffe75abe1902e 100644
--- a/src/compiler/schedule.h
+++ b/src/compiler/schedule.h
@@ -22,6 +22,7 @@ namespace internal {
 namespace compiler {
 
 class BasicBlock;
+class BasicBlockInstrumentor;
 class Graph;
 class ConstructScheduleData;
 class CodeGenerator;  // Because of a namespace bug in clang.
@@ -278,6 +279,7 @@ class Schedule : public GenericGraph<BasicBlock> {
 
  private:
   friend class ScheduleVisualizer;
+  friend class BasicBlockInstrumentor;
 
   void SetControlInput(BasicBlock* block, Node* node) {
     block->control_input_ = node;