OOP PDF - Add OpenPDFParamsParser class

This patch introduces OpenPDFParamsParser class which is responsible
to parse open pdf parameters and set them in a dictionary. This
dictionary will be used to set initial viewport settings when opening
pdf document.

BUG=303491

Review URL: https://codereview.chromium.org/477933003

Cr-Commit-Position: refs/heads/master@{#292360}
2 files changed