[Merge to XFA] Minor documentation updates for fpdfview.h.

[Merge to XFA] Minor documentation updates for fpdfview.h.

This does some minor copy editing and formatting of the documentation in the
fpdfview.h header.

R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1411863004 .

(cherry picked from commit 19169dae5bf92813b7419793f61dfca8b4fb9124)

Committed: https://pdfium.googlesource.com/pdfium/+/49f88b708d905b052bc00769ac7cb48202cac019

[dsinclair, 2015-10-20 18:29:20]

PTAL.

The merge was not clean. Had to add in a few flags from master that didn't exist
on xfa. There is a string structure on XFA that doesn't exist on master and a
few note sections added about the form stuff that I merged.

[dsinclair, 2015-10-20 18:31:32]

Description was changed from

==========
Minor documentation updates for fpdfview.h.

This does some minor copy editing and formatting of the documentation in the
fpdfview.h header.

R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1411863004 .

(cherry picked from commit 19169dae5bf92813b7419793f61dfca8b4fb9124)
==========

to

==========
[Merge to XFA] Minor documentation updates for fpdfview.h.

This does some minor copy editing and formatting of the documentation in the
fpdfview.h header.

R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1411863004 .

(cherry picked from commit 19169dae5bf92813b7419793f61dfca8b4fb9124)
==========

[Tom Sepez, 2015-10-20 19:02:41]

lgtm

[dsinclair, 2015-10-20 19:18:54]

Committed patchset #1 (id:1) manually as
49f88b708d905b052bc00769ac7cb48202cac019 (presubmit successful).