Convert string Find methods to return an Optional

The Find and ReverseFind methods for WideString, WideStringC,
ByteString, and ByteStringC have been converted from returning a raw
FX_STRSIZE, to returning Optional<FX_STRSIZE>, so that success/failure
can be indicated without using FX_STRNPOS.

This allows for removing FX_STRNPOS and by association makes the
conversion of FX_STRSIZE to size_t easier, since it forces checking
the return value of Find to be explictly done as well as taking the
error value out of the range of FX_STRSIZE.

New Contains methods have been added for cases where the success or
failure is all the call site to Find cared about, and the actual
position was ignored.

BUG=pdfium:828


Change-Id: Id827e508c8660affa68cc08a13d96121369364b7
Reviewed-on: https://pdfium-review.googlesource.com/11350
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 2 insertions, 4 deletions

diff --git a/core/fpdfapi/parser/fpdf_parser_utility.cpp b/core/fpdfapi/parser/fpdf_parser_utility.cpp
index 7cea16569f..a36d640da3 100644
--- a/core/fpdfapi/parser/fpdf_parser_utility.cpp
+++ b/core/fpdfapi/parser/fpdf_parser_utility.cpp
@@ -89,7 +89,7 @@ int32_t GetDirectInteger(CPDF_Dictionary* pDict, const CFX_ByteString& key) {
 }
 
 CFX_ByteString PDF_NameDecode(const CFX_ByteStringC& bstr) {
-  if (bstr.Find('#') == FX_STRNPOS)
+  if (!bstr.Contains('#'))
     return CFX_ByteString(bstr);
 
   int size = bstr.GetLength();
@@ -110,9 +110,7 @@ CFX_ByteString PDF_NameDecode(const CFX_ByteStringC& bstr) {
 }
 
 CFX_ByteString PDF_NameDecode(const CFX_ByteString& orig) {
-  if (orig.Find('#') == FX_STRNPOS)
-    return orig;
-  return PDF_NameDecode(orig.AsStringC());
+  return orig.Contains("#") ? PDF_NameDecode(orig.AsStringC()) : orig;
 }
 
 CFX_ByteString PDF_NameEncode(const CFX_ByteString& orig) {