[cleanup] remove unused ExpectedStubMiss

Bug: 
Change-Id: I0cc16f129dc4bd49abd04b8f6fa22102dab61c9b
Reviewed-on: https://chromium-review.googlesource.com/691655Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48214}

src/code-stubs.cc

@@ -28,11 +28,6 @@ namespace internal {
 
 using compiler::CodeAssemblerState;
 
-RUNTIME_FUNCTION(UnexpectedStubMiss) {
-  FATAL("Unexpected deopt of a stub");
-  return Smi::kZero;
-}
-
 CodeStubDescriptor::CodeStubDescriptor(CodeStub* stub)
     : isolate_(stub->isolate()),
       call_descriptor_(stub->GetCallInterfaceDescriptor()),

src/counters.h

@@ -829,9 +829,7 @@ class RuntimeCallTimer final {
   V(StringLengthGetter)                        \
   V(TestCounter1)                              \
   V(TestCounter2)                              \
-  V(TestCounter3)                                   \
-  /* Dummy counter for the unexpected stub miss. */ \
-  V(UnexpectedStubMiss)
+  V(TestCounter3)
 
 #define FOR_EACH_HANDLER_COUNTER(V)              \
   V(KeyedLoadIC_LoadIndexedStringStub)           \