Add a getSelectedText method to the PDF plugin.
Add a getSelectedText method to the PDF plugin.

Review URL: https://codereview.chromium.org/617163002

Cr-Commit-Position: refs/heads/master@{#297649}
(cherry picked from commit 7c23f3fc46a1e368780b2b6d7e0e2b183d3645d8)

BUG=419427

Review URL: https://codereview.chromium.org/621143002

Cr-Commit-Position: 6a5bd00280c7717eac32edec8cb53cab00a8776a@{#36}
Cr-Branched-From: 1c214a52100f31060d23fd0ab193aa06dd7def74@{#297060}

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