Revert "inline String#to_sym"

This reverts commit 4e5c02f.

Author: Nicolas Laurent

src/main/java/org/truffleruby/core/inlined/CoreMethods.java

@@ -87,7 +87,6 @@ public class CoreMethods {
     public final InternalMethod STRING_BYTESIZE;
     public final InternalMethod MODULE_CASE_EQUAL;
     public final InternalMethod STRING_EQUAL;
-    public final InternalMethod STRING_TO_SYM;
     public final InternalMethod SYMBOL_TO_PROC;
     public final InternalMethod ARRAY_AT;
     public final InternalMethod ARRAY_INDEX_GET;
@@ -154,7 +153,6 @@ public CoreMethods(RubyContext context) {
         KERNEL_KIND_OF = getMethod(kernelModule, "kind_of?");
         MODULE_CASE_EQUAL = getMethod(moduleClass, "===");
         STRING_EQUAL = getMethod(stringClass, "==");
-        STRING_TO_SYM = getMethod(stringClass, "to_sym");
         SYMBOL_TO_PROC = getMethod(symbolClass, "to_proc");
         ARRAY_AT = getMethod(arrayClass, "at");
         ARRAY_INDEX_GET = getMethod(arrayClass, "[]");
@@ -213,8 +211,6 @@ public RubyNode createCallNode(RubyCallNodeParameters callParameters, Translator
                     return InlinedIsNilNodeGen.create(context, callParameters, self);
                 case "bytesize":
                     return InlinedByteSizeNodeGen.create(context, callParameters, self);
-                case "to_sym":
-                    return InlinedToSymNodeGen.create(context, callParameters, self);
                 default:
             }
         } else if (n == 2) {

src/main/java/org/truffleruby/core/inlined/InlinedToSymNode.java

@@ -172,7 +172,6 @@
 import org.truffleruby.language.control.RaiseException;
 import org.truffleruby.language.dispatch.DispatchNode;
 import org.truffleruby.language.library.RubyLibrary;
-import org.truffleruby.language.methods.Split;
 import org.truffleruby.language.objects.AllocateHelperNode;
 import org.truffleruby.language.objects.WriteObjectFieldNode;
 import org.truffleruby.language.yield.YieldNode;
@@ -2493,12 +2492,6 @@ public abstract static class ToSymNode extends CoreMethodArrayArgumentsNode {
 
         @Child RopeNodes.CodeRangeNode codeRangeNode = RopeNodes.CodeRangeNode.create();
 
-        public static ToSymNode create() {
-            return StringNodesFactory.ToSymNodeFactory.create(null);
-        }
-
-        public abstract RubySymbol execute(RubyString string);
-
         @Specialization(
                 guards = { "!isBrokenCodeRange(string, codeRangeNode)", "equalNode.execute(string.rope,cachedRope)" },
                 limit = "getDefaultCacheLimit()")