Revert "Revert "Revert "Unhandled exception handler based on local ref counti…"

[architkulkarni]

Reverts #14113

There are some build failures on master:

ERROR: /Users/travis/build/ray-project/ray/BUILD.bazel:705:8: Couldn't build file _objs/memory_store_test/memory_store_test.pic.o: C++ compilation of rule '//:memory_store_test' failed (Exit 1): wrapped_clang failed: error executing command 
645  (cd /private/var/tmp/_bazel_travis/7c557718f3877739c657a427203800b1/execroot/com_github_ray_project_ray && \
646  exec env - \
647    APPLE_SDK_PLATFORM=MacOSX \
648    APPLE_SDK_VERSION_OVERRIDE=10.13 \
649    LANG=en_US.UTF-8 \
650    LC_ALL=en_US.UTF-8 \

See https://travis-ci.com/github/ray-project/ray/jobs/483318121#L661

src/ray/core_worker/test/memory_store_test.cc:47:3: error: ignoring return value of function declared with 'warn_unused_result' attribute [-Werror,-Wunused-result]
provider->Get({id1}, 1, 100, context, false, &results);
^~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~