Reverting 3174. Aka reapplying 3150, 3151 and 3159. Aka api accessor

src/code-stubs.h

Index: src/code-stubs.h
diff --git a/src/code-stubs.h b/src/code-stubs.h
index 121140d1bae670b1a364d100024bcf2815163c45..63461bc0c09d6a3592282297bcc4240935f900a4 100644
--- a/src/code-stubs.h
+++ b/src/code-stubs.h
@@ -75,6 +75,7 @@ class CodeStub BASE_EMBEDDED {
 #define DEF_ENUM(name) name,
     CODE_STUB_LIST(DEF_ENUM)
 #undef DEF_ENUM
+    NoCache,  // marker for stubs that do custom caching
     NUMBER_OF_IDS
   };
 
@@ -91,6 +92,12 @@ class CodeStub BASE_EMBEDDED {
 
   virtual ~CodeStub() {}
 
+  // Override these methods to provide a custom caching mechanism for
+  // an individual type of code stub.
+  virtual bool GetCustomCache(Code** code_out) { return false; }
+  virtual void SetCustomCache(Code* value) { }
+  virtual bool has_custom_cache() { return false; }
+
  protected:
   static const int kMajorBits = 5;
   static const int kMinorBits = kBitsPerInt - kSmiTagSize - kMajorBits;