Revert^4 "JIT JNI stubs."

The original CL,
    https://android-review.googlesource.com/513417 ,
has a bug fixed in the Revert^2,
    https://android-review.googlesource.com/550579 ,
and this Revert^4 adds two more fixes:
    - fix obsolete native method getting interpreter
      entrypoint in 980-redefine-object,
    - fix random JIT GC flakiness in 667-jit-jni-stub.

Test: testrunner.py --host --prebuild --no-relocate \
      --no-image --jit -t 980-redefine-object
Bug: 65574695
Bug: 69843562

This reverts commit 056d7756152bb3ced81dd57781be5028428ce2bd.

Change-Id: Ic778686168b90e29816fd526e23141dcbe5ea880
diff --git a/runtime/managed_stack-inl.h b/runtime/managed_stack-inl.h
index 689dd80..678be8e 100644
--- a/runtime/managed_stack-inl.h
+++ b/runtime/managed_stack-inl.h
@@ -24,7 +24,7 @@
 namespace art {
 
 inline ShadowFrame* ManagedStack::PushShadowFrame(ShadowFrame* new_top_frame) {
-  DCHECK(top_quick_frame_ == nullptr);
+  DCHECK(!HasTopQuickFrame());
   ShadowFrame* old_frame = top_shadow_frame_;
   top_shadow_frame_ = new_top_frame;
   new_top_frame->SetLink(old_frame);
@@ -32,7 +32,7 @@
 }
 
 inline ShadowFrame* ManagedStack::PopShadowFrame() {
-  DCHECK(top_quick_frame_ == nullptr);
+  DCHECK(!HasTopQuickFrame());
   CHECK(top_shadow_frame_ != nullptr);
   ShadowFrame* frame = top_shadow_frame_;
   top_shadow_frame_ = frame->GetLink();