[turbofan] Add support for inlining of builtins.

src/compiler.h

Index: src/compiler.h
diff --git a/src/compiler.h b/src/compiler.h
index 2f1d3335e5f9985e0304860283d62731e5b9acfa..d4657055cc55cd60949557f790b90539e54c1634 100644
--- a/src/compiler.h
+++ b/src/compiler.h
@@ -167,7 +167,8 @@ class CompilationInfo {
     kDisableFutureOptimization = 1 << 20,
     kModule = 1 << 21,
     kToplevel = 1 << 22,
-    kSplittingEnabled = 1 << 23
+    kSplittingEnabled = 1 << 23,
+    kBuiltinInliningEnabled = 1 << 24
   };
 
   CompilationInfo(Handle<JSFunction> closure, Zone* zone);
@@ -294,6 +295,12 @@ class CompilationInfo {
 
   bool is_inlining_enabled() const { return GetFlag(kInliningEnabled); }
 
+  void MarkAsBuiltinInliningEnabled() { SetFlag(kBuiltinInliningEnabled); }
+
+  bool is_builtin_inlining_enabled() const {
+    return GetFlag(kBuiltinInliningEnabled);
+  }
+
   void MarkAsTypingEnabled() { SetFlag(kTypingEnabled); }
 
   bool is_typing_enabled() const { return GetFlag(kTypingEnabled); }