[turbofan] Insert dummy values when changing from None type.

src/bailout-reason.h

Index: src/bailout-reason.h
diff --git a/src/bailout-reason.h b/src/bailout-reason.h
index 0966334ffa4c6ee03b743515ab06a97f18823271..31122a5c82b43bbd35392ee162425bfa9228768a 100644
--- a/src/bailout-reason.h
+++ b/src/bailout-reason.h
@@ -267,9 +267,7 @@ namespace internal {
   V(kWrongArgumentCountForInvokeIntrinsic,                                     \
     "Wrong number of arguments for intrinsic")                                 \
   V(kShouldNotDirectlyEnterOsrFunction,                                        \
-    "Should not directly enter OSR-compiled function")                         \
-  V(kConversionFromImpossibleValue,                                            \
-    "Reached conversion from value with empty type (i.e., impossible type)")
+    "Should not directly enter OSR-compiled function")
 
 #define ERROR_MESSAGES_CONSTANTS(C, T) C,
 enum BailoutReason {