Revert of Traverse PDF page tree only once in CPDF_Document Try 2

Revert of Traverse PDF page tree only once in CPDF_Document Try 2 (patchset #3 id:40001 of https://codereview.chromium.org/2442403002/ )

Reason for revert:
Not quite right yet.

Original issue's description:
> Traverse PDF page tree only once in CPDF_Document
> 
> Try 2: main fix was recursively popping elements from the stack. Since
> the Traverse method can be called on non-root nodes from GetPage(), we
> have to make sure to properly update the parents.
> 
> Try 1 at https://codereview.chromium.org/2414423002/
> 
> In our current implementation of CPDF_Document::GetPage, we traverse
> the PDF page tree until we find the index we are looking for. This is
> slow when we do calls GetPage(0), GetPage(1), ... since in this case
> the page tree will be traversed n times if there are n pages. This CL
> makes sure the page tree is only traversed once.
> 
> Time to load the PDF from the bug below in chrome official build:
> Before this CL: around 1 minute 25 seconds
> After this CL: around 4 seconds
> 
> BUG=chromium:638513
> 
> Committed: https://pdfium.googlesource.com/pdfium/+/d3a2009d75eac3cda442f545ef0865afae7b35cf

TBR=tsepez@chromium.org,weili@chromium.org,thestig@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:638513
Committed: https://pdfium.googlesource.com/pdfium/+/900f421e29daf2ab62de3ae8dc821f031bc7bdb3

[npm, 2016-10-28 21:10:40]

The CQ bit was checked by npm@chromium.org

[npm, 2016-10-28 21:10:41]

Created Revert of Traverse PDF page tree only once in CPDF_Document Try 2

[commit-bot: I haz the power, 2016-10-28 21:10:50]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Tom Sepez, 2016-10-28 21:13:07]

RS LGTM

[commit-bot: I haz the power, 2016-10-28 21:30:49]

Description was changed from

==========
Revert of Traverse PDF page tree only once in CPDF_Document Try 2 (patchset #3
id:40001 of https://codereview.chromium.org/2442403002/ )

Reason for revert:
Not quite right yet.

Original issue's description:
> Traverse PDF page tree only once in CPDF_Document
> 
> Try 2: main fix was recursively popping elements from the stack. Since
> the Traverse method can be called on non-root nodes from GetPage(), we
> have to make sure to properly update the parents.
> 
> Try 1 at https://codereview.chromium.org/2414423002/
> 
> In our current implementation of CPDF_Document::GetPage, we traverse
> the PDF page tree until we find the index we are looking for. This is
> slow when we do calls GetPage(0), GetPage(1), ... since in this case
> the page tree will be traversed n times if there are n pages. This CL
> makes sure the page tree is only traversed once.
> 
> Time to load the PDF from the bug below in chrome official build:
> Before this CL: around 1 minute 25 seconds
> After this CL: around 4 seconds
> 
> BUG=chromium:638513
> 
> Committed:
https://pdfium.googlesource.com/pdfium/+/d3a2009d75eac3cda442f545ef0865afae7b...

TBR=tsepez@chromium.org,weili@chromium.org,thestig@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:638513
==========

to

==========
Revert of Traverse PDF page tree only once in CPDF_Document Try 2 (patchset #3
id:40001 of https://codereview.chromium.org/2442403002/ )

Reason for revert:
Not quite right yet.

Original issue's description:
> Traverse PDF page tree only once in CPDF_Document
> 
> Try 2: main fix was recursively popping elements from the stack. Since
> the Traverse method can be called on non-root nodes from GetPage(), we
> have to make sure to properly update the parents.
> 
> Try 1 at https://codereview.chromium.org/2414423002/
> 
> In our current implementation of CPDF_Document::GetPage, we traverse
> the PDF page tree until we find the index we are looking for. This is
> slow when we do calls GetPage(0), GetPage(1), ... since in this case
> the page tree will be traversed n times if there are n pages. This CL
> makes sure the page tree is only traversed once.
> 
> Time to load the PDF from the bug below in chrome official build:
> Before this CL: around 1 minute 25 seconds
> After this CL: around 4 seconds
> 
> BUG=chromium:638513
> 
> Committed:
https://pdfium.googlesource.com/pdfium/+/d3a2009d75eac3cda442f545ef0865afae7b...

TBR=tsepez@chromium.org,weili@chromium.org,thestig@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:638513

Committed:
https://pdfium.googlesource.com/pdfium/+/900f421e29daf2ab62de3ae8dc821f031bc7...
==========

[commit-bot: I haz the power, 2016-10-28 21:30:50]

Committed patchset #1 (id:1) as
https://pdfium.googlesource.com/pdfium/+/900f421e29daf2ab62de3ae8dc821f031bc7...