[arm64] Avoid external reference for abort in embedded builtins

This CL uses segfaulting instructions in embedded builtins, instead of
a trap handler which require relocation and can hence not be used in
embedded builtins.

Bug: v8:7985, v8:6666

Change-Id: I87776785602f13d15f565d49b2332eb2adc62bd4
Reviewed-on: https://chromium-review.googlesource.com/1151192
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54724}

src/arm64/macro-assembler-arm64.cc

@@ -3000,6 +3000,13 @@ void TurboAssembler::Abort(AbortReason reason) {
   TmpList()->Combine(MacroAssembler::DefaultTmpList());
 
   if (should_abort_hard()) {
+    // TODO(7985): Isolate independent builtins cannot tolerate external
+    // references, so we just provoke a segfault to indicate the error.
+    if (options().isolate_independent_code) {
+      Move(x1, 0);
+      Ldr(x1, MemOperand(x1));
+      return;
+    }
     // We don't care if we constructed a frame. Just pretend we did.
     FrameScope assume_frame(this, StackFrame::NONE);
     Mov(w0, static_cast<int>(reason));