The legacy function declaration locations from Annex B 3.2 and 3.4 do not
apply for generator declarations. This patch cracks down on those usages,
which is tested for by new incoming test262 tests.

BUG=v8:4824
LOG=Y
R=adamk

Review-Url: https://codereview.chromium.org/1900033003
Cr-Commit-Position: refs/heads/master@{#35835}