[regexp] Fix up includes for noi18n builds

The breaking change was
https://chromium-review.googlesource.com/c/v8/v8/+/1658157

Bug: v8:9359
Change-Id: I6fa956631a8e475123cf6f8f44e66f2c499d47b7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1660627
Auto-Submit: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62207}

src/regexp/regexp-compiler-tonode.cc

@@ -4,6 +4,7 @@
 
 #include "src/regexp/regexp-compiler.h"
 
+#include "src/execution/isolate.h"
 #include "src/regexp/jsregexp.h"
 #include "src/strings/unicode-inl.h"
 #include "src/utils/splay-tree-inl.h"

src/regexp/regexp-compiler.cc

@@ -10,6 +10,7 @@
 #include "src/regexp/jsregexp.h"  // TODO(jgruber): Only needed for IgnoreCase.
 #include "src/regexp/regexp-macro-assembler-arch.h"
 #include "src/regexp/regexp-macro-assembler-tracer.h"
+#include "src/strings/unicode-inl.h"
 #include "src/utils/ostreams.h"
 #include "src/utils/splay-tree-inl.h"
 #include "src/zone/zone-list-inl.h"