[compiler] Remove obsolete guard in MarkForOptimization.

The guard in JSFunction::MarkForOptimization checking whether a function
is being debugged is overly protective. The compilation pipeline will
bailout itself in that circumstance. Having the runtime behave similar
makes sure the debugger observes a situation closer to reality.

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/1900743003

Cr-Commit-Position: refs/heads/master@{#35625}

src/objects.cc

@@ -11974,12 +11974,9 @@ bool JSFunction::Inlines(SharedFunctionInfo* candidate) {
 
 void JSFunction::MarkForOptimization() {
   Isolate* isolate = GetIsolate();
-  // Do not optimize if function contains break points.
-  if (shared()->HasDebugInfo()) return;
   DCHECK(!IsOptimized());
   DCHECK(shared()->allows_lazy_compilation() ||
          !shared()->optimization_disabled());
-  DCHECK(!shared()->HasDebugInfo());
   set_code_no_write_barrier(
       isolate->builtins()->builtin(Builtins::kCompileOptimized));
   // No write barrier required, since the builtin is part of the root set.