Previously the inlining of accessors into try-blocks (i.e. try/catch,
try/finally, for-of, etc.) was disabled in JSNativeContextSpecialization,
which prevented a couple of interesting optimizations, i.e. we end up
with a LOAD_IC in optimized code for this simple example:

  class A { get x() { return 1; } }
  function foo(a) {
    try {
      return a.x;
    } catch (e) {
      return 0;
    }
  }
  foo(new A)

This is now fixed and the accessors are properly rewired into the
handler chain.

BUG=v8:6278,v8:6344,v8:6424
R=jarin@chromium.org

Review-Url: https://codereview.chromium.org/2902533003
Cr-Commit-Position: refs/heads/master@{#45485}