Check that the names buffer is not empty before passing to GetNameFromTT.

Check that the names buffer is not empty before passing to GetNameFromTT.
Due to implicit conversion if the names buffer is empty then nullptr will
be passed to GetNameFromTT which blindly dereferences it leading to a NPD
if an invalid font file is read.

BUG=583037
Patch by forshaw@

R=tsepez@chromium.org

Committed: https://pdfium.googlesource.com/pdfium/+/73733f079c086562d8e7c2943ed16cf6f95b2c42

[forshaw, 2016-03-03 00:25:22]

forshaw@chromium.org changed reviewers:
+ tsepez@chromium.org

[forshaw, 2016-03-03 00:25:23]

PTAL.

[Tom Sepez, 2016-03-03 00:26:17]

lgtm

[Oliver Chang, 2016-03-03 00:36:59]

Description was changed from

==========
Check that the names buffer is not empty before passing to GetNameFromTT.
Due to implicit conversion if the names buffer is empty then nullptr will
be passed to GetNameFromTT which blindly dereferences it leading to a NPD
if an invalid font file is read.

BUG=583037
==========

to

==========
Check that the names buffer is not empty before passing to GetNameFromTT.
Due to implicit conversion if the names buffer is empty then nullptr will
be passed to GetNameFromTT which blindly dereferences it leading to a NPD
if an invalid font file is read.

BUG=583037

Patch by forshaw@
==========

[Tom Sepez, 2016-03-03 01:38:11]

Description was changed from

==========
Check that the names buffer is not empty before passing to GetNameFromTT.
Due to implicit conversion if the names buffer is empty then nullptr will
be passed to GetNameFromTT which blindly dereferences it leading to a NPD
if an invalid font file is read.

BUG=583037

Patch by forshaw@
==========

to

==========
Check that the names buffer is not empty before passing to GetNameFromTT.
Due to implicit conversion if the names buffer is empty then nullptr will
be passed to GetNameFromTT which blindly dereferences it leading to a NPD
if an invalid font file is read.

BUG=583037

Patch by forshaw@

R=tsepez@chromium.org

Committed:
https://pdfium.googlesource.com/pdfium/+/73733f079c086562d8e7c2943ed16cf6f95b...
==========

[Tom Sepez, 2016-03-03 01:38:12]

Committed patchset #1 (id:1) manually as
73733f079c086562d8e7c2943ed16cf6f95b2c42 (presubmit successful).