Kill unused IPDF_ classes.

Kill unused IPDF_ classes.

Some are simply never defined.  Some are never instantiated.  Some have
paths that are never reached.

R=thestig@chromium.org

Committed: https://pdfium.googlesource.com/pdfium/+/80b597d3f32ef2509627c7561abb84a6f5ac09bf

[Tom Sepez, 2015-06-02 22:19:26]

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

[Tom Sepez, 2015-06-02 22:19:29]

Lei, more cleanup.

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdfapi/fpdf_m...
File core/include/fpdfapi/fpdf_module.h (left):

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdfapi/fpdf_m...
core/include/fpdfapi/fpdf_module.h:123: class IPDF_FontMgr;
note: IPDF_FontMgr is removed.

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdfapi/fpdf_p...
File core/include/fpdfapi/fpdf_parser.h (left):

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdfapi/fpdf_p...
core/include/fpdfapi/fpdf_parser.h:95: void					EnumPages(IPDF_EnumPageHandler*
pHandler);
note: only reference to IPDF_EnumPageHandler, and its never called.

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdfapi/fpdf_r...
File core/include/fpdfapi/fpdf_render.h (left):

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdfapi/fpdf_r...
core/include/fpdfapi/fpdf_render.h:136: class IPDF_BackgroundDraw
Note: never instantiated, set, etc.

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdfapi/fpdf_r...
core/include/fpdfapi/fpdf_render.h:237: class IPDF_PageImageCache
Note: unused.

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdfdoc/fpdf_t...
File core/include/fpdfdoc/fpdf_tagged.h (left):

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdfdoc/fpdf_t...
core/include/fpdfdoc/fpdf_tagged.h:15: class IPDF_ReflowEngine;
note: unused.

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdftext/fpdf_...
File core/include/fpdftext/fpdf_text.h (right):

https://codereview.chromium.org/1168503003/diff/1/core/include/fpdftext/fpdf_...
core/include/fpdftext/fpdf_text.h:15: class IPDF_LinkExtract;
note: just some tidying.

[Lei Zhang, 2015-06-02 22:44:55]

lgtm

[Tom Sepez, 2015-06-03 23:09:18]

Committed patchset #1 (id:1) manually as
80b597d3f32ef2509627c7561abb84a6f5ac09bf (presubmit successful).