[regexp] Return compile data from VerifyRegExpSyntax

Embarrassingly, while integrating VerifyRegExpSyntax into SpiderMonkey,
I realized that I had refactored away the RegExpCompileData* argument,
which is necessary for emitting error messages when parsing fails.

Bug: v8:10406
Change-Id: Iaa8cd1f944bbf058ccc03c052b5ec0563b7c2e99
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2219415Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68033}

src/regexp/regexp-parser.cc

@@ -1833,10 +1833,10 @@ bool RegExpParser::ParseRegExp(Isolate* isolate, Zone* zone,
 bool RegExpParser::VerifyRegExpSyntax(Isolate* isolate, Zone* zone,
                                       FlatStringReader* input,
                                       JSRegExp::Flags flags,
+                                      RegExpCompileData* result,
                                       const DisallowHeapAllocation& no_gc) {
   RegExpParser parser(input, flags, isolate, zone);
-  RegExpCompileData dummy;
-  return parser.Parse(&dummy, no_gc);
+  return parser.Parse(result, no_gc);
 }
 
 RegExpBuilder::RegExpBuilder(Zone* zone, JSRegExp::Flags flags)

src/regexp/regexp-parser.h

@@ -161,6 +161,7 @@ class V8_EXPORT_PRIVATE RegExpParser {
                           JSRegExp::Flags flags, RegExpCompileData* result);
   static bool VerifyRegExpSyntax(Isolate* isolate, Zone* zone,
                                  FlatStringReader* input, JSRegExp::Flags flags,
+                                 RegExpCompileData* result,
                                  const DisallowHeapAllocation& no_gc);
 
  private: