This makes sure the {AstGraphBuilder} respects the catch-prediction that
is provided by the parser along with each {TryStatement}. This is needed
for try-blocks materialized by the parser not to influence predictions
users expect when using the debugger.

R=neis@chromium.org
TEST=mjsunit/debug-exceptions
BUG=v8:5183

Review-Url: https://codereview.chromium.org/2147573002
Cr-Commit-Position: refs/heads/master@{#37702}