Revert "[turbofan] enable switch jump tables with --no-untrusted-code-mitigations,"

This reverts commit 884bec9f.

Reason for revert: https://logs.chromium.org/v/?s=chromium%2Fbb%2Fclient.v8%2FV8_Linux64_TSAN%2F20938%2F%2B%2Frecipes%2Fsteps%2FCheck%2F0%2Flogs%2Fgraceful_shutdown%2F0

Original change's description:
> [turbofan] enable switch jump tables with --no-untrusted-code-mitigations,
> also for stubs and Wasm
> 
> Bug: chromium:845851
> Change-Id: I9b860dc26f8b35d629235b82fc5fffe04bf10493
> Reviewed-on: https://chromium-review.googlesource.com/1076151
> Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#53525}

TBR=mstarzinger@chromium.org,jarin@chromium.org,tebbi@chromium.org,ben.titzer@gmail.com

Change-Id: If24709e40bc6c442b88c8ba7b804775a9dfafc15
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:845851
Reviewed-on: https://chromium-review.googlesource.com/1087467Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53529}

src/optimized-compilation-info.cc

@@ -62,9 +62,6 @@ OptimizedCompilationInfo::OptimizedCompilationInfo(
 #endif
   SetTracingFlags(
       PassesFilter(debug_name, CStrVector(FLAG_trace_turbo_filter)));
-  if (!FLAG_turbo_disable_switch_jump_table) {
-    SetFlag(kSwitchJumpTableEnabled);
-  }
 }
 
 OptimizedCompilationInfo::OptimizedCompilationInfo(

src/optimized-compilation-info.h

@@ -63,7 +63,7 @@ class V8_EXPORT_PRIVATE OptimizedCompilationInfo final {
   OptimizedCompilationInfo(Zone* zone, Isolate* isolate,
                            Handle<SharedFunctionInfo> shared,
                            Handle<JSFunction> closure);
-  // Construct a compilation info for stub compilation, Wasm, and testing.
+  // Construct a compilation info for stub compilation (or testing).
   OptimizedCompilationInfo(Vector<const char> debug_name, Zone* zone,
                            Code::Kind code_kind);
 

src/wasm/wasm-code-manager.cc

@@ -271,7 +271,6 @@ void WasmCode::Validate() const {
       case RelocInfo::WASM_STUB_CALL:
       case RelocInfo::JS_TO_WASM_CALL:
       case RelocInfo::EXTERNAL_REFERENCE:
-      case RelocInfo::INTERNAL_REFERENCE:
       case RelocInfo::INTERNAL_REFERENCE_ENCODED:
       case RelocInfo::OFF_HEAP_TARGET:
       case RelocInfo::COMMENT: