Prepare to add a use counter for Intl.v8BreakIterator

Source/bindings/core/v8/V8PerIsolateData.cpp

Index: Source/bindings/core/v8/V8PerIsolateData.cpp
diff --git a/Source/bindings/core/v8/V8PerIsolateData.cpp b/Source/bindings/core/v8/V8PerIsolateData.cpp
index d5aa45c6d7d8f79c13d732112242c2243266d8d0..bfca715e18ab407bc1631c1be874600e8220e350 100644
--- a/Source/bindings/core/v8/V8PerIsolateData.cpp
+++ b/Source/bindings/core/v8/V8PerIsolateData.cpp
@@ -57,7 +57,10 @@ static void useCounterCallback(v8::Isolate* isolate, v8::Isolate::UseCounterFeat
         UseCounter::count(currentExecutionContext(isolate), UseCounter::UseAsm);
         break;
     default:
-        ASSERT_NOT_REACHED();
+        // V8 may be a newer version that has some use counters we don't know
+        // about yet. FIXME: Add support for v8::Isolate::kBreakIterator and
+        // UseCounter::BreakIterator.
+        break;
     }
 }