Use CFX_WideString in CPDF_NameTree functions to strip BOMchromium/3162

PDFium doesn't strip BOMs during parsing, but we should strip BOMs when
retrieving parsed strings in CPDF_NameTree to ensure consistency and
appropriate function behavior. See the bug for more info.

As outlined in Bug=pdfium:593, the solution is to call GetUnicodeText()
instead of GetString(). I added a GetUnicodeTextAt() function in
CPDF_Array, which is symmetrical to GetUnicodeTextFor() in
CPDF_Dictionary.

I then changed the input variable types to CPDF_NameTree functions to
be CFX_WideString instead of CFX_ByteString, and modified all the
calls to them.

I also added a unit test for nametree, which would fail prior to this
change. Nametrees with non-unicode names are already tested by embedder
tests.

Bug=pdfium:820

Change-Id: Id69d7343632f83d1f5180348c0eea290f478183f
Reviewed-on: https://pdfium-review.googlesource.com/8091
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: Jane Liu <janeliulwq@google.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/fpdfsdk/javascript/Document.cpp b/fpdfsdk/javascript/Document.cpp
index d5b075da62..ba4b2ae622 100644
--- a/fpdfsdk/javascript/Document.cpp
+++ b/fpdfsdk/javascript/Document.cpp
@@ -1594,13 +1594,12 @@ bool Document::gotoNamedDest(CJS_Runtime* pRuntime,
     return false;
   }
   CFX_WideString wideName = params[0].ToCFXWideString(pRuntime);
-  CFX_ByteString utf8Name = wideName.UTF8Encode();
   CPDF_Document* pDocument = m_pFormFillEnv->GetPDFDocument();
   if (!pDocument)
     return false;
 
   CPDF_NameTree nameTree(pDocument, "Dests");
-  CPDF_Array* destArray = nameTree.LookupNamedDest(pDocument, utf8Name);
+  CPDF_Array* destArray = nameTree.LookupNamedDest(pDocument, wideName);
   if (!destArray)
     return false;