In addition to Parser, other phases (such as scope analysis) need to handle
compilation errors in the future. PendingCompilationErrorHandled takes care of
error handling in a unified way.

Split from https://codereview.chromium.org/943543002/ .

R=rossberg@chromium.org
BUG=

Review URL: https://codereview.chromium.org/960543002

Cr-Commit-Position: refs/heads/master@{#26853}