Update to V8 with partial snapshots. This is taken from the partial_snapshot branch of V8.
diff --git a/src/code-stubs.h b/src/code-stubs.h
index 16267f6..d502f14 100644
--- a/src/code-stubs.h
+++ b/src/code-stubs.h
@@ -100,7 +100,7 @@
   static int MinorKeyFromKey(uint32_t key) {
     return MinorKeyBits::decode(key);
   };
-  static const char* MajorName(Major major_key);
+  static const char* MajorName(Major major_key, bool allow_unknown_keys);
 
   virtual ~CodeStub() {}
 
@@ -138,7 +138,7 @@
   virtual InLoopFlag InLoop() { return NOT_IN_LOOP; }
 
   // Returns a name for logging/debugging purposes.
-  virtual const char* GetName() { return MajorName(MajorKey()); }
+  virtual const char* GetName() { return MajorName(MajorKey(), false); }
 
 #ifdef DEBUG
   virtual void Print() { PrintF("%s\n", GetName()); }