Bug fix for polymorphic inlining.

The code used to wrongly propagate try/catch information to
new blocks. Since it has the same logic as Hraph::InlineInto,
extract the code that updates loop and try/catch information
to blocks to a shared method.

bug:27330865
bug:27372101
bug:27360329

(cherry picked from commit a1d8ddfa)

Change-Id: Ice0373ec0a1c24d78121634a377f6f502e814cfb