[ignition] Mark switches as being side-effect free

Bug: v8:6218
Change-Id: I53806585ee2ba5ea5bc49748a659cceb2eeaf501
Reviewed-on: https://chromium-review.googlesource.com/506668
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45337}

src/interpreter/bytecodes.h

@@ -626,7 +626,7 @@ class V8_EXPORT_PRIVATE Bytecodes final {
     return (IsAccumulatorLoadWithoutEffects(bytecode) ||
             IsRegisterLoadWithoutEffects(bytecode) ||
             IsCompareWithoutEffects(bytecode) || bytecode == Bytecode::kNop ||
-            IsJumpWithoutEffects(bytecode));
+            IsJumpWithoutEffects(bytecode) || IsSwitch(bytecode));
   }
 
   // Returns true if the bytecode is Ldar or Star.