Introduce runtime function %OptimizeFunctionOnNextCall to manually trigger optimization.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 874dcbc902ea0111d5f49b756f774df7c4b35af4..106042d2cb99f90b46ffadfec519d8259a318501 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -4534,6 +4534,9 @@ class JSFunction: public JSObject {
   // Tells whether or not this function has been optimized.
   inline bool IsOptimized();
 
+  // Tells whether or not this function can be optimized.
+  inline bool IsOptimizable();
+
   // Mark this function for lazy recompilation. The function will be
   // recompiled the next time it is executed.
   void MarkForLazyRecompilation();