Simpler regex names:

runtime/vm/regexp_assembler_ir.cc

Index: runtime/vm/regexp_assembler_ir.cc
diff --git a/runtime/vm/regexp_assembler_ir.cc b/runtime/vm/regexp_assembler_ir.cc
index bd04d7f56b5b471b714686cea46548b0974395aa..6f656dbb9e86573ecc157815f5d92ba451ef7645 100644
--- a/runtime/vm/regexp_assembler_ir.cc
+++ b/runtime/vm/regexp_assembler_ir.cc
@@ -311,7 +311,7 @@ bool IRRegExpMacroAssembler::CanReadUnaligned() {
 
 
 RawArray* IRRegExpMacroAssembler::Execute(
-    const JSRegExp& regexp,
+    const RegExp& regexp,
     const String& input,
     const Smi& start_offset,
     Zone* zone) {
@@ -429,7 +429,7 @@ ConstantInstr* IRRegExpMacroAssembler::StringConstant(const char* value) const {
 ConstantInstr* IRRegExpMacroAssembler::WordCharacterMapConstant() const {
   const Library& lib = Library::Handle(Z, Library::CoreLibrary());
   const Class& regexp_class = Class::Handle(Z,
-        lib.LookupClassAllowPrivate(Symbols::JSSyntaxRegExp()));
+        lib.LookupClassAllowPrivate(Symbols::_RegExp()));
   const Field& word_character_field = Field::ZoneHandle(Z,
       regexp_class.LookupStaticField(Symbols::_wordCharacterMap()));
   ASSERT(!word_character_field.IsNull());